- In some GM trucks, a blower motor control module failure can cause the front blower motor to stop working or run after the vehicle has been shut off. The GM bulletin 06-01-39-002C describes this problem that happens in cold weather. The bulletin advises replacing the blower motor control module.
What can cause a blower motor to stop working?
In most cases, a blower motor resistor fails due to corrosion or overheating. Sometimes, the mechanical resistance to the motor rotation causes an excessive electric current that can overheat and prematurely damage the blower motor resistor.
How do I know if my blower motor resistor is bad?
Bad Blower Motor Resistor Symptoms
- Only One Speed From Blower Motor. One of the most common symptoms of trouble with the blower motor resistor is when the fan gets stuck in one setting.
- Various Airflow Settings Not Working.
- No Air Coming From Vents.
Is there a fuse for the blower motor?
Many vehicles have two fuses for the blower motor, one in the interior fuse block and the other under the hood. The blower motor is usually under the dashboard on the passenger side.
What are the symptoms of a bad blower motor relay?
If you have a faulty blower motor, you may experience low airflow from the vents, even when the fan is on high. There will be no air coming from the vents if your fan isn’t working due to a bad blower motor resistor.
How do I reset my blower motor?
How to Find and Reset your Furnace Motor Blower
- Step 1: Turn off the power to the furnace.
- Step 2: Remove the blower compartment cover.
- Step 3: Make sure the blower is completely cooled off.
- Step 4: Locate the reset button.
- Step 5: Press the button in (assuming that this is your issue and that the button has popped).
Can you drive without a blower motor?
Your car’s blower motor is not only necessary for the operation of your air conditioner. Without a functioning blower motor your engine runs the risk of overheating. Start car and see if blower motor works. If fuse blows again, check for loose circuits.
What happens when the blower motor resistor goes out?
If the resistor shorts or fails, it may cause the blower motor to remain stuck on one fan speed. The heating and air conditioning systems may still function at one speed, however the resistor will have to be replaced in order for full functionality to be restored.
How do I test a blower motor resistor?
Place one lead of the Ohmmeter on terminal 1 of the resistor. Place the other lead on terminal 2 and check against specifications. If this circuit is open, showing infinity on the Ohmmeter, the blower resistor must be replaced. Move the lead from terminal 2 to terminal 3 and check this reading against specifications.
Where is the blower motor relay fuse located?
The blower relay is located near the front of the fuse block and is labeled ‘Blower.’ Inspect the center of the relay. If the metal rod inside is broken, the relay will need to be replaced.
Where is the relay for the blower motor?
The blower motor relay is generally located in the under-hood fuse box or in the under-dash fuse box. A blown fuse can mimic relay failure.
Why will a blower run on the on position and not on auto?
Other Blower Fan Won’t Run Problems The fan will run and blow warm air but only in FAN or FAN ON mode – delivering heat – but NOT in AUTO mode. This is a bad temperature sensor in the unit; replace the fan limit controller.
Blower motor doesn’t work GM
GM has published a service bulletinPIT5343 to address a condition in which the Blower Motor does not operate or does not change speeds when the vehicle is first started. The following cars are affected by the bulletin: Colorado Chevrolet Silverado 1500 2014 Chevrolet Silverado 1500 2015 Chevrolet Silverado 1500 Sierra 1500 (2014 model year) and Canyon (2015 model year) HVAC is operated manually (RPO C67 or C42)
Also interesting: Blower motor doesn’t work GM? (Correct answer)
How the blower motor problem appears
If you own one of the cars mentioned above and observe that the blower motor does not operate when the engine is started or that the blower motor does not change speeds, do not replace the blower motor, switches, or resistor. Instead, replace the blower motor, switches, and resistor. This is a software bug that can cause the HVAC control head to become unresponsive if the following procedure is followed: 1. The engine is running, and 2. The blower motor is operating. 3. The HVAC system is in Defrost mode, and the defrost light is illuminated.
After completing this procedure, the blower motor will not operate when you restart the machine and will not respond when you attempt to modify the blower motor speed.
Alternatively, turn the blower motor knob.
In the year 2017, Rick Muscoplat is a professional musician.
blower not working on 5
If the blower motor speed resistor has to be changed, there is a good possibility that the high speed blower relay has gone bad as well. GM offers a kit to replace the speed resistor and wire harness for the blower motor, which is prone to burning out or shorting out on a regular basis. Good luck, and please keep us informed. You’ll also need to change the wire harness for the Resistor. There is a GM Tech Bulletin on this. The resistor generates an overheating problem, and the stock harness does not have the required AWG, resulting in the wires catching on fire.
- The bad news is that it’s a GM-only part number, and they’re $95.00 on the open market.
- A/C – Blower motor is not working or is only working at a low speed.
- : 05-01-38-012C Bulletin No.
- Please toss it out.
- 05-01-38-012B (Corporate Bulletin) (Section 01 – HVAC).
- Remove Corporate Bulletin Number 05-01-38-012B from your records (Section 01 – HVAC).
- Correction REPLACE THE RESISTOR FOR THE BLOWER MOTOR AS WELL AS THE RESISTOR MODULE CONNECTOR.
The following are examples of fullsize trucks and utility vehicles: Htr A/CHVAC 1 fuses are used Fuse 35 for the Blower is situated in the Underhood Fuse Block of Midsize Utility Vehicles.
Connect the connection to the resistor module and remove it from the circuit.
Ensure that the wires are cut back far enough from the connection to ensure that any melted insulation on the wire is eliminated.
Use the proper crimping tool from the terminal repair kit J 38125 to ensure a proper seal.
It is possible that other splice sleeves will not adequately protect the splice from moisture or will not create a satisfactory electrical connection.
Use the yellow splice sleeves that came with the connection to join the wires.
Replace the blower motor resistor with a new one. Replace the fuse or connection block if it has been removed. Check that the blower motor operates at all speeds by running it through its paces. Reinstall the hush panel/close-out panel if it has been removed.
Replaced blower motor resistor now blower motor wont work
I’ve gone down this path before and have done a lot of research on it. My 2013 2500 Suburban began experiencing problems with the air conditioning only working sometimes. Because the Blower Motor always tested well, I’d replace out the Resistor whenever possible. It would work for a short period of time before failing completely. I’d try another one, and sometimes it’d work, and other times it didn’t. It was frustrating. In the end, I replaced the old AC compressor with a new one. Our issue was just sporadic, and the store was unable to reproduce the symptoms.
- Afterwards, I read something regarding battery cables/power cables degrading with time and producing strange difficulties with your electrical system, as well as with your air conditioner’s blower motor and resistor on rare occasions.
- For all of the cables, the dealership demanded a hefty sum of money from me (I think I did 4 different cables- positive and negative, one to the alternator, and one to the fuse box, and maybe I did the ground too).
- Everything was resolved as a result of this.
- Since then, I have not had a single issue with my air conditioning.
- I’m not sure whether this would be of use, however it appears that certain power lines were prone to failing at some point.
- Best of luck.
- But, at the very least, I finished it.
Chevrolet AC Blower Control Problems Solved at FixMyOldRide.com
Replacement Kit for the control of an air conditioner’s blower Troubleshooting and repair for typical AC blower control module issues. A problem with inconsistent interior fan performance has been reported by drivers of numerous popular Chevrolet pickup trucks and sport utility vehicles. In fact, there was one instance in which the blower fan remained on high long after the ignition key was removed. However, it appears that the most frequently reported issue is that the fan does not respond to speed adjustments or does not operate at all.
- The GMC versions of these pickups, such as the Envoy and Yukon, are, of course, exempt from this rule.
- Some could argue that this isn’t a classic ride because it’s so new.
- I was working at a Chevrolet dealership during the time these vehicles were still covered by the manufacturer’s warranty.
- An interesting point to mention is that consumers who complained about this problem without receiving a resolution had their condition documented while their product was still under warranty since no defect was discovered.
When the problem grew widespread, clients were given the option of extending their warranties and receiving the covered repairs.
Updated AC Control Module Parts
Unfortunately, we were unable to provide you with the updated components today. This section will cover the new and enhanced components of the second design, as well as some best practices for pinpoint diagnostics and installation. Although pricing may vary from one region of the country to the next, I can tell you that if you brought your car into a dealership, this repair would likely cost a couple of hundred dollars. New AC blower control modules are available for as little as $60, making the replacement of the module a do-it-yourself project for many technicians.
AC Blower Control Module Malfunction
Now that we’ve reached the section of the article that discusses the complaint, the reason, and the solution, we need to clarify something. A blower control module may only be installed in a vehicle equipped with automatic temperature control, also known as ATC. This is the digital type, which operates in the same way as the HVAC control panel in your home. As soon as you set the thermostat to 70 degrees, the climate control system automatically changes the temperature doors and blower speed to match your preferences.
A blower resistor assembly will be installed in its place.
However, it is critical that you are aware of the distinction and understand what elements are in the automotive.
Diagnosing a Defective Blower Control Module
Diagram of the Blower Motor Control Module The blower module is accessed from the passenger side floorboard region of the autos we’re talking about. It is possible that a hush panel will need to be removed in order to obtain access to the compartment. Another thing to keep in mind is that on certain vehicles, the glove box will swing out of the way to allow for easier access. The only thing you have to do is press up on the stop tab located in the upper left corner of the glove box compartment to activate it.
- Despite the fact that you most likely have a faulty AC blower control module, you should do a few simple checks before purchasing replacement parts for the unit.
- The fact that they have blown indicates that the module is consuming an excessive amount of energy.
- Despite the fact that it is most probable that you have a module problem, it is still possible that the blower motor is faulty.
- If you have done so and the fan is still not spinning, give it a little tap on the motor housing to see if it will begin to spin on its own.
- You will almost certainly not have electricity at the blower motor.
- Consider the blower control module to be a sort of intermediary.
- The AC blower control module is faulty if you have power and ground coming into the unit but nothing coming out when the maximum blower setting is chosen on the control panel.
If there is no power coming from the three-wire module connector, it is possible that there is a problem with the air conditioning control head.
The Control Module Replacement Parts
As I indicated in the introduction, a revised replacement module is available. Despite the fact that the part seems to be considerably different from the original, it is designed to fit directly into the existing mounting spot with no modifications required. The region around the heat sink that prevents the gadget from overheating can be seen to be one of the most significant modifications in the new design. Aside from that, the replacement part has a different connector configuration, which means that we’ll have to splice the three wires from the control head that we tested before.
- For your own safety, you should remove the battery from the vehicle.
- What would happen?
- It is not the end of the world, but chances are you don’t have one on hand, and a new one will cost you roughly five dollars, so it is not the best of times.
- Make careful to cut each wire individually to avoid blowing any fuses.
- This implies that you’ll have to go to your local auto parts store and get some replacements.
- In this case, though, it’s definitely overkill, because not everyone has access to a soldering station.
Final Thoughts about this Blower Motor Problem
Blower motor resistor failures have been reported in a large number of automobiles manufactured in the early 2000s. Not only are Chevrolet goods affected by this issue, but so are Dodge vehicles and even certain international automobiles, according to the information provided. Heat accumulation appears to be the root cause of the problem. Most of the automobiles that have these problems now have replacement components that have greater heat sinks to disperse the heat that has accumulated. In order to avoid repeating this repair, you should only have to do it once throughout the course of your ownership.
There is a potential that the blower motor is the source of the problem in the first place.
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Blower motor, resistor: how it works, symptoms, problems, testing
The most recent update was on August 1, 2021. In automobiles, a blower motor is a type of motor that drives the fan in the vehicle’s heating and air conditioning system. It is usually found inside the dash, on the opposite side of the steering wheel, or inside the engine compartment, on the firewall, depending on the vehicle. It is the blower motor resistor, also known as the blower motor control module, that is in charge of controlling the blower motor’s rotational speed. What exactly is the distinction?
It is used in automobiles if the blower motor has just four or five fixed speeds, as seen on the left side of this picture.
As seen in the photograph, an electronic blower motor control module is installed in cars equipped with an automated temperature control system and vehicles in which the blower speed may be changed gradually.
This is done in order to allow air to circulate around the resistor or control module, allowing it to cool down.
Blower motor resistor / control module problems
In many automobiles, problems with the blower motor resistor are prevalent. Generally speaking, the most typical sign of a failed blower motor resistor is that the heater fan only operates at the maximum speed level (4 or 5) and does not operate at lower speed settings. In some automobiles, a faulty blower motor resistor can cause the heater fan to stop functioning altogether in rare instances. The majority of the time, a blower motor resistor fails as a result of corrosion or overheating. Mechanical resistance to motor rotation can occasionally result in an excessive electric current flowing through the motor, causing it to overheat and prematurely destroy the blower motor resistor.
Problems with a blower motor control module are less common, but they occur for the same reasons: corrosion or overheating when the motor is blocked or shorted, for example.
Occasionally, a faulty blower control module or processor can cause the blower motor to continue operating even after the ignition is turned off in some vehicles (e.g., older General Motors trucks).
How is the blower motor resistor diagnosed?
The rust in this Ford blower motor resistor has caused it to fail. Diagnostic procedures differ from one another. A visual check of the resistor will frequently uncover the source of the problem. Examples include the failure of the blower motor resistor in a Ford Escape due to corrosion, as shown in this photograph of the vehicle. The resistance between the resistor’s terminals must be tested and compared to the manufacturer’s requirements if there is no visible damage to the resistor. If the resistance is not within specifications, the resistor will need to be changed.
According to the service handbook, the resistance should be between 4-5 ohms.
In our scenario, the ohmmeter indicates that the resistor has failed, which signifies that the resistor has failed.
This indicates that after replacing the blower motor resistor, you should check to see if the blower motor is running smoothly and without making any noise.
This was a prevalent problem in earlier Chrysler and Dodge minivans, for example. In this scenario, it is also necessary to replace the blower motor. When a blower motor is worn out, it might make a loud screeching noise occasionally while operating, which is one of the signs of the problem.
How to test the blower motor?
Corrosion has caused this Ford blower motor resistor to fail. Procedures for diagnosing a disease differ from one another. An examination of the resistor will frequently uncover the source of the problem. Examples include the failure of the blower motor resistor in a Ford Escape due to corrosion, as shown in this photograph of a Ford Escape. It is necessary to examine the resistance between the resistor’s terminals and compare it to the manufacturer’s requirements if there is no visible damage.
- Example: In this snapshot, the resistance of a blower motor resistor was measured and recorded for future reference.
- With the help of an ohm-meter, a faulty resistor was identified.
- In certain cases, the failure of a blower motor resistor is caused by issues with the blower motor.
- Occasionally, a worn-out blower motor might cause a previously replaced resistor to fail again, which is something we have witnessed.
- A new blower motor will be required in this situation.
How is the blower motor control module tested?
A scan tool, which is used by mechanics at dealerships, may be used to diagnose the HVAC system. If you do not have access to a scan tool, many automobiles with automated climate control systems have a self-testing or diagnostic mode that you may use instead. Typically, it may be initiated by pressing and holding various buttons at the same time. According to the service handbook for the 2009 Honda Accord, the following is how the process should be performed: Set the ignition to the ‘ON’ position.
- Once in the self-diagnostic mode, the system will display a fault code on the display if there is a problem.
- The testing technique for each code is described in detail in the service manual.
- Another method is to check the voltage at the blower motor, the blower motor control module, and other sections of the circuit in accordance with the service instructions for the particular model.
- Honda power transistor is being tested (blower motor control module).
- The power transistor has four wires: two come from the temperature control system control unit, one is for ground, and one is for the negative terminal of the blower motor.
- The service handbook recommends checking the voltage at the blower motor first, and if that is not satisfactory, checking the voltage at the power transistor and so on.
- According to Honda advisory 03-048, a fault with the blower motor for the rear HVAC system in the 2003 Pilot was characterized as not working at all speeds when the vehicle was started.
- BMW refers to the blower motor control module as a Final Stage Unit, and it is likewise a component that is prone to failure.
- More information may be found in the followingYouTube videos.
- This condition, which occurs in cold weather, is described in detail in General Motors bulletin 06-01-39-002C.
According to the notice, the blower motor control module should be replaced. It is referred to as the Linear Power Module by General Motors (LPM). More information may be found in the followingYouTube videos.
Repair options
Your neighborhood mechanic or any small repair business should be able to determine the source of the malfunction. Of course, scheduling an appointment with your dealer is the most expedient option. A large number of dealers have the component in stock. The cost of replacing the blower motor resistor or control module is not prohibitively high. A coworker of ours, for example, had an issue with his 2011 Ford Escape, which had a fan that only operated at speed 4. In the end, he spent $50 for the diagnosis and $112 for the resistor replacement at a local Ford shop.
- The blower motor resistor is found on top of the HVAC unit, behind the glove box, in the Ford Escape / Mazda Tribute from 2008 to 2011 model years.
- It’s kept in place by two screws and is simple to swap out.
- The blower motor resistor is likewise positioned beneath the glove box in the Ford F150, however it is mounted on the right side of the plastic air duct in the model years 2008 to 2011.
- It was written by the author of this site on his experience changing the blower motor resistor in a Jeep Liberty.
How the blower motor resistor works
The blower resistor schematic shown below demonstrates how the blower motor resistor is linked in a typical automobile. In this vehicle, the resistor is bypassed when the fan speed is set to the maximum ‘4’ level, and the blower motor is driven directly by the fan switch. Therefore, if the resistor is damaged, the blower motor may continue to operate at the ‘High’ speed setting in some vehicles.In this diagram, the fan switch is set to speed ‘1,’ and the blower motor current is reduced by three resistors (R2, R3, and R4) connected in series with the blower motor voltage.
When several resistors are connected in series, the total resistance increases and is equal to the sum of the individual resistances.
Amazon.com: AC Heater Blower Motor – Compatible with Chevy, GMC & Other GM Vehicles – Silverado, Tahoe, Avalanche, Suburban, Escalade, Sierra, Yukon, H2 – Replaces 15-81683, 22741027, 20760618, 700164 – ATC : Automotive
On September 27, 2019, a review was conducted in the United States. Purchase that has been verified I was pleased with how quickly and inexpensively I received the items. However, when I attempted to install the fan, I discovered a serious flaw in the process. Asymmetrically spaced fins characterize both the original fan and this replacement, allowing it to only be pointed in one direction. It’s not difficult at all. The original fan’s fins, on the other hand, featured a little ramp molded into the tip of the fin, which caused the fin to rise and lock into place when the fan was revolved.
- In reality, I was unable to generate enough upward pressure throughout the installation process to compensate for the lack of ramps.
- A little ramp was eased onto the leading edge of each fin using a file, and there was the solution.
- After all is said and done, it’s an excellent value for a completely functional fan, but this issue may force a less technically minded consumer to return it in disgust.
- The review will take place in the United States on July 8, 2020.
- This would not go in until I squared up the corners on both sides.
- Although it may have been excellent for others, it did not fit my 2005 GMC Yukon XL until it was changed.
- 3.0 stars out of 5 for this product Installation necessitates some tweaking, but it is otherwise flawless.
John wrote: The tabs are almost identical to the OEM component, with the exception that the edges of the tabs are slanted rather than straight.
Photograph shows the original with square corners on the tab, as well as the tool I used to make the modifications to the new tab.
Would have gotten 5 stars if it had fit out of the box, but I only gave it 3 since many people would be quite annoyed attempting to install it and may not have access to a dremel or other tool to readily change the tabs.
Purchase that has been verified This was installed in a 2009 GMC Sierra 2500HD.
The image I submitted shows one tab that has been edited and one that has not been touched.
It goes perfectly in with the modification, and it doesn’t with out it.
Once all of the drama has been resolved.
3.0 stars out of 5 for this product Tab ramps are on the incorrect side of the screen; a mod is necessary to keep the game running smoothly.
This was installed in a 2009 GMC Sierra 2500HD.
The image I submitted shows one tab that has been edited and one that has not been touched.
It goes perfectly in with the modification, and it doesn’t with out it.
Once all of the drama has been resolved.
The photographs in this review The product was reviewed in the United States on December 12, 2019 and it was verified as a purchase.
It was not going to rotate.
I took the motor housing apart and soldered it together myself.
Fortunately, I had the necessary equipment and skills to repair and install it.
***GARBAGE PRODUCT*** received a rating of 1.0 out of 5 stars.
It did not function at all!
posted a message.
It was not going to rotate.
I took the motor housing apart and soldered it together myself.
Fortunately, I had the necessary equipment and skills to repair and install it.
***GARBAGE PRODUCT*** The images in this review are of garbage products.
Amazon mentioned that this partially fit, which is correct in that a section of it actually physically fit.
I was a little irritated.
That particular port has been banned.
I was a little irritated.
Verified Purchase on December 5, 2020 in the United States of America My 2013 Silverado Z71 (LT, automatic temperature control) was able to accommodate this after undergoing the following adjustment, which another buyer described: Before installing the blower, I used a Dremel with a cutting bit to smooth down the leading edge of the tabs on the flange.
- After I made the necessary modifications, the blower was a breeze to install.
- The replacement does not appear to be an exact replica of the original, but it does the job.
- Installation is straightforward, and the product is a direct replacement for the 2011 GMC Sierra 2500.
- High is more accurately described as medium high.
- It goes away after a few minutes, and it appears to be burning something plastic at the time of starting.
- Verified Purchase This was something I had to learn the hard way.
- When I pulled the resistor, it appeared to be damaged.
- The blower motor began to spin.
- Then everything stopped working again.
It would have been better if I had replaced both the resistor and the blower motor in one go. It is not costly, yet it is really necessary on a hot day (s). The original blower and resistor were in service for 14 years. I shouldn’t have had to replace one of these with a robe again.
Top reviews from other countries
a rating of 2.0 out of 5 stars It didn’t fit Chevrolet Silverado 2009 On December 24, 2019, a reviewer in Canada stated that the purchase was verified. The blower is functional, however it will not fit a 2009 Silverado. Possibly with a little filing, but I’m not going to mess with a new component that is intended to fit perfectly. Returned. 5.0 stars out of 5 for this product It’s blowing fantastic right now. Reviewed in Canada on December 5, 2019Verified Purchase with prompt delivery. The fit was perfect.
- When you replace the blower motor, don’t forget to replace the resistor pac as well.
- Purchased on October 22, 2020 in Canada and reviewed on October 22, 2020 Blower fan for GMC Sierra 1500 that is a great fit.
- I used YouTube to assist with the installation.
- 4.0 stars out of 5 for this product Blower Motor for Central Air Conditioning On January 10, 2021, a reviewer in Canada commented on the purchase.
- 1.0 out of 5 starsThe product has been damaged.
- Both the box and the merchandise were damaged.
- I’m not sure who was at fault, but I was really dissatisfied with the packaging.
- Both the box and the merchandise were damaged.
- I’m not sure who was at fault, but I was really dissatisfied with the packaging.
Blower motor issue
I can’t seem to get this connector to come apart for the life of me. I know this is the source of the problem because when I press it or attempt to unplug it, the blower turns back on. There is a good chance that the connection plastic melted partially and the two parts fused together. In this specific case, the connections (on the blower pigtail) are composed of super-cheap, supple nylon material. It is possible that you may have to be really forceful with it, but this will be extremely perilous.
What’s more, you’re already aware that at least one of the two parts (male and female) is inherently evil.
More information about the topic, as well as debate, can be found here: Moreover, here is the procedure for repairing it with the manufacturer ‘upgrade’ kit (which I have not done myself) The use of resistors in conjunction with the connection was only a ‘small detail’ that saved money on the overall project.
Which would have been good in and of itself, except that the seller backed out at the last minute.
In any case, resistors are almost never used in automobiles today since most of them utilize a continuous control knob (with an electronic driving circuit behind the knob) instead.
The simplest solution, without a doubt, would be to get the GM kit (albeit I have no personal experience with it).
But (and this is just because you brought it up.) (I’m not suggesting that you do or don’t anything.) However, you could completely remove the connection and splice the wire ends together.
You could separate the resistors from the connector and solder wires to them in order to join them in the new spliced connection, but this is not recommended.
You could easily look for the heater blower speed-control resistors in another car if you have a spare set lying around.
It may be necessary to extend the wires a few inches in order to tuck it away up under there, depending on where you can find a suitable location nearby.
In fact, the majority of resistor clusters you’ll come across will be at least twice as physically hefty as the whimpy little resistor cluster that’s on the 355 blower connector (i.e., twice the maximum wattage rating).
The resistance of the non-original equipment replacement need not be identical to the original equipment resistance.
However, if they are significantly different, it is possible that it will not work because any difference will cause the blower speed to vary.
There are a couple of candidates out there who won’t cost you much money to try out if you are in the mood to experiment.
The thing is, it will eventually do the same thing.
Due to the fact that they are sleeved bushings, the motor will begin to draw more current as they wear down in order to compensate for the additional drag.
Resistors from other vehicles, on the other hand, could differ significantly from one vehicle to the next because they are dependent on the size and current draw of the blower motor.
I’ve written down the resistance of the three resistors in some handwritten notes.
(If this is of any assistance to anyone) It is possible to deal with the problem directly if you are willing to do away with the unnecessary OE piece.
Typically, the resistors themselves are not the source of the problem.
The connector is the source of the problem.
You can save the original resistors and separate them from the connector (which is no longer there because you spliced it out), and they will continue to function for many years after that.
It’s worth noting that the typical type resistors (found in a slew of other vehicles over the years) that have the resistors mounted separately nearby are made with thicker terminals that would be easier to wire to in a retro-fit mod, if that’s where you went with it.
(all the rest is the interwiring between the resistors and the switch to get the motor to ground) Bet supermod can whip out a kit to do this on any given night when he’s up late and can’t sleep.
I’d do one myself but I suspect everyone who cares already has the GM retrofit patch kit._ Don’t know how readable the schematics are for you/anyone else, but the blower schematic is ‘AC Blower.pdf’ if you open the zip file.
Looking at it from top down, the blower motor is connected directly (at the top connection) to it’s +12 volts source.
It’s path toward ‘ground’ in other words.
that is, as you connect each into the chain by rotating the switch -back towards 0, it adds more resistance and that slows the motor.
From there though it’s through the switch.
That Splice-Pack is the one on the passenger side, behind the airbox.]] On the schematic.
see that it branches to both the resistor-chain (on the right) and the FAN speed switch (to the left) (to the left).
On speed -4- the resistors are not in the circuit, the path is straight to the switch and from there through the traveling part of the switch to ground (-12 volts) (-12 volts).
It can get so that it won’t run at all though.
That plastic connector is the tall box you see to the right around the resistor chain where the 4 wires show the little arrows.
The arrows are the pins (male/female). The way it’s drawn it doesn’t appear to be in the circuit between the fan and the switch, but it is. The drawing is pretty well-done and clear, but in that aspect it fools the eye a bit. Not that it’s wrong, it just isn’t obvious/clear in that way.