Why does my GMC heater blower not work?

I have replaced the black bosch relay behind the glovebox, the blower resistor and the blower motor and still cannot get the blower to work on high. I remember in older model years of gmc’s and chevys that their was a high speed blower relay that caused this issue. If there is a high speed relay, I can’t find it. Any suggestions?

What to do if your blower motor only works on high speed?

If your blower only operates on its highest speed, chances are you have the series type of blower motor resistor. This is the most common failure mode. To repair the problem, simply replace the resistor block. It’s usually located in the ductwork (to keep the coils cool) below the glove box.

Why does the Chevy Avalanche blower keep blowing?

The auto climate control fan speed is controlled via PWM with a solid-state driver. Completely different system, and different issue. I am running into a similar issue. 2003 Avalanche, fan keeps blowing even after engine is off, fan turns on and off intermittently. Dual climate control.

Why does my heater not work on high speed?

Heater blower motor will not work on high speed? I have replaced the black bosch relay behind the glovebox, the blower resistor and the blower motor and still cannot get the blower to work on high. I remember in older model years of gmc’s and chevys that their was a high speed blower relay that caused this issue.

What kind of blower does not work on high?

1997 GMC C1500 Heater/AC Blower Will Not Work on HIGH. 1997 GMC C1500 Heater/AC blower will not work on HIGH. I have replaced the black BOSCH relay behind the glovebox, the blower RESISTOR and the blower MOTOR and still cannot get the blower to work on HIGH.

Why did my Chevy Silverado blower plug burn up?

Most aftermarket companies, NAPA CARQUEST ADVANCE will have replacement plugs you can splice in for about half the price of a GM plug kit, and they burn up because GM cheaped out on the size of the terminals and they get hot, when they get hot they loose tension which causes them the get really hot and melt the plastic plug.

Why is my Silverado Sierra blowing cold air?

After fiddling with the controls a bit I gave up and rolled the windows down. About five minutes later it was eating at me so I switched the control from off to max and the fan kicked on like it was supposed to and was blowing cold air.

Is there an under hood blower motor relay?

Under hood relay box has an AC relay that is a 4 prong relay and blower motor relay is a 5 prong relay. Any idea where else it might be?

What to do if your heater fan does not work?

Now gently grab ahold of the red and black wire connector and wiggle it if your fan came on you have found the problem. Now if this worked for you remove the positive battery wire from the battery because the red wire at this connector remains hot.

Why is my air conditioning not working on my GMC Sierra?

While there are a variety of reasons your GMC Sierra 1500 air conditioning won’t work, the most common 3 are a refrigerant leak, an electrical climate control issue, or a problem with the air conditioning compressor.

Why does my Silverado Sierra not have a fan?

I only use the truck to go to the lumber yard, so I just let it be – until today, when it was 98F and I got stuck in a 10-mile traffic jam (I said many bad words). Dashboard switches appear normal, but a/c clutch does not engage. (Is this properly called a “cycling switch”?) Do not know whether the fan switch was on or off when tested.

Why is my a / C blower not blowing?

A metal that when it corrodes, it turns white, and unlike copper, aluminum corrosion does not conduct electricity at all and causes resistance issues and can cause overheating of a circuit. Took out a common finger nail Emory board and went to work, both sides of each contact, then used a small brass brush on each side and along the tips.

Why is my C-1500 AC not working?

If it’s low enough, the compressor will not even kick in. Just a thought before you start tearing things apart. Thanks. I only have an old R-12 gauge set, so I can’t actually test the refrigerant level.

Why does my AC blower motor work intermittently?

Intermittent electrical problems can make you feel like your a blind man trying to catch a stray dog. You can’t post conmments that contain an email address.

Where is the blower motor on a Dodge van?

Will either replace it or, in the interim, will have to grease the shaft of the motor. The blower motor on a 1999 Dodge Ram VAN 1500 is located (when facing the front of the vehicle) below the AC/Heater Core box on the left side) along with the Blower Motor Resistor mounted into the side of that box.

Why does my blower not come on when I start my truck?

Since then, every once in a while I notice that the fan doesn’t come on when I start the truck, or if it does it’s very weak, so I crank it to max, the fan blows noticeably, then I turn it down to a more reasonable setting.

Why is my blower not working on my GMC Sierra 1500?

The connector that plugs into the blower motor under the glove box became too hot and melted the plastic resulting in the a/c and heat not to work (this includes the windshield defroster).

Why does my GMC heater not work on high?

1997 GMC C1500 Heater/AC blower will not work on HIGH. I have replaced the black BOSCH relay behind the glovebox, the blower RESISTOR and the blower MOTOR and still cannot get the blower to work on HIGH. I remember in older model years of GMC’s and Chevys that their was a high speed blower relay that caused this issue.

Intermittent electrical problems can make you feel like your a blind man trying to catch a stray dog. You can’t post conmments that contain an email address.

What happens if the blower motor only works on high speed?

In other designs, the failure of 1 resistor means you lose only one speed. However, most car makers bypass the blower motor resistor completely when you move the fan speed switch to high. If your blower only operates on its highest speed, chances are you have the series type of blower motor resistor. This is the most common failure mode.

What causes a bad or failing blower motor relay?

Blown fuses. One of the first symptoms of a bad or failing AC blower motor relay is a blown AC blower motor relay circuit fuse. If the blower motor relay develops any sort of problem that hinders its ability to properly limit and distribute power, it may cause the blower motor fuse to blow. Any sort of electrical spikes or excessive current…

Where is the blower control switch on the dashboard?

The blower control switch on the dashboard controls the circuit flow of the blower motor to adjust the voltage from low, to medium, to medium-high, to high. When on high, the circuit bypasses the blower resistor.

What to do if your Chevy blower motor relay blows out?

The blower motor relay on your Chevy vehicle is essential for the operation of the blower. If the relay is blown out, you will need to install a new one is soon as you can. Thankfully, it is fairly simple to tell if the relay is malfunctioning and to install a replacement.

Is there a high speed blower motor relay?

Yes there is a high speed relay which sounds like it is out. Here is a guide to help test it and the blower motor wiring diagrams so you can see how the system works with the relay location below as well. Check out the diagrams (Below).

Why does my air conditioner and heater stop working?

However, if you’re experiencing problems from the HVAC controls, then it’s possible that the same issue will prevent both your air conditioning and heater from working. For instance, a failed blower motor won’t be able to blow air into the cabin. A failed fan switch will make it impossible to adjust the blower fan speed.

What to do when your AC Fan is not working?

Checked for incoming resistance ground to the blower, from the dash control switch and it works. Checked for battery at the blower, when the car is running. There is no battery to operate the blower. Rotated all the PDC relays around, they have the same ID, other than ABS pump.

Why are the heater controls on my truck not working?

Went out to start the truck and the heater controls were black wont come on no heat or ac. I have checked the fuses all good I have also put two new controls in and nothing.

Why is my blower motor only working at high speed?

The first thing that needs to be determined is the type of noise that is present and the possible sources. Rattling or knocking noises while… The blower motor only working on high speed is a common symptom of a failing blower motor resistor; but the fact the radio stopped working at the same time is unusual.

What to do if your blower is not working?

The very first step you need to take is getting a scan run on the computer. Take your car to a technician or a local parts store and have them scan the car. They will give you a list of… Hello there, thank you for asking about your 1998 Oldsmobile LSS.

Why is my AC heater fan not working?

This sounds more like a problem with high speed fan relay. On the low speeds, the fan relay routes the voltage thru the resistor block. When you switch to high fan speed, the relay switches over to supply full voltage from the battery to the fan motor.

Why does my Astro AC fan not work?

My 91 Chevy Astro doesn’t like to blow air on high. The AC/Heater fan works fine at lower settings but when in high it doesn’t work at all or will run for 30 seconds and then stop. I’ve replaced the switch in the dash, but that didn’t help.

Why is my GMC Sierra 1500 heater not working?

While there are a variety of reasons your GMC Sierra 1500 heater is not working, the most common 3 are a broken heater blower motor, a problem with the thermostat, or a failed heater blower motor resistor.

Why is my F150 heater fan not working?

When a Blower Resistor fails it can fail in many ways. 1 being the fan won’t turn off unless you pull a fuse 2. you may only have one speed as i suffered high or nothing. 3. you have may not have any fan at all. while there is many reasons for this to fail which includes high resistance in the blower motor. Loading…

What to do if your Ford Fusion heater is not working?

When the blower motor resistor fails, the air conditioner and heater may still work, but air may blow from the vents at only some of the fan speed settings. If the resistor isn…

What happens when the blower fails on a Chevy Equinox?

When the blower motor fails, the air conditioner and heater may still work, and heat or cool may be felt at the vents, but the air pressure will be dramatically decreased. This Read More When the heater control valve fails, adjusting the temperature may not change the air temperature at the vents, whether hot or cold.

Under hood relay box has an AC relay that is a 4 prong relay and blower motor relay is a 5 prong relay. Any idea where else it might be?

What happens if you have a bad blower motor?

The blower motor is the component responsible for pushing air through the vents of your vehicle’s heating and air conditioning systems. Without it, the AC system will not be able to circulate any heated or cooled air.

What causes a blower motor to stop working?

In a situation where the motor doesn’t work on any speed, the most likely causes are: a blown power supply fuse, a bad motor ground connection, bad motor speed control module or a failed motor. On all systems, a failed blower motor is least likely. Blower motors generally don’t fail out of the clear blue.

What to do if your blower motor relay is failing?

For this reason, if you suspect that your blower motor relay is having a problem, have the vehicle’s AC system diagnosed by a professional technician from YourMechanic. They will be able to determine if the car will need a blower motor relay replacement, or a different repair, to bring full functionality back to your AC system.

How do you fix a blower motor on a car?

Disconnect the electrical connector at the blower motor and jumper power and ground to the motor, bypassing all the speeds controls. Run a fused jumper from the battery to the power side of the motor and connect a temporary grounding jumper to the other motor terminal.

Where is the high speed fan on a Silverado Sierra?

That must be it behind the glovebox. Pulled the connector off, still had the high only speed. The high setting must be a direct connection to the motor. I’ll work on it more tomorrow.

Why is my AC fan not working on my Silverado?

As suspected there’s continuity on all the resistors but what appears to be a diode or fuse is open. Seems the circuit was previously replaced, the screws were not very tight. It is likely the blower is causing the failure. However, the new resistor you put in…

Why does my blower fan only work on one speed?

by Lee Sallings. The most common symptom of a faulty blower motor resistor is a blower fan that only works on one speed, usually high. This can be annoying, but troubleshooting is easy. If you start at the blower motor, and check resistance in the circuit, you will find the problem in no time.

That must be it behind the glovebox. Pulled the connector off, still had the high only speed. The high setting must be a direct connection to the motor. I’ll work on it more tomorrow.

When to replace the heater fan control switch?

If you have replaced the blower motor and blower motor resistor on your ’95-’98 GM truck or SUV, and your fan only works on high or doesn’t turn on at all, your heater fan control switch needs to be replaced. This video explains on how to do replace this part. Thanks for watching. Loading…

What kind of blower resistor do GMC pickups use?

NOTE: This tutorial only applies to the 1988 to 1993 vehicles listed in the ‘Applies To:’ box on the right column. Some 1994 Chevy/GMC pickups use this type of blower resistor. For the 1995 and newer blower resistor test, the following tutorial will help:

Which is the best GMC heater blower motor?

Shop AutoZone for GMC C1500 A/C Heater Blower Motor. 10% OFF $75. Use Code: DIYSAVE10 Online Ship-to-Home Orders Only

Why does my Silverado Sierra have no fan?

The failure mode on these is one or two of the resistors blow and you end up with just a few of the fan speeds or as previously mentioned the connector burns up and you have no fan speeds. Powered by phpBB © phpBB Group. phpBB Mobile / SEO by Artodia .

Shop AutoZone for GMC C1500 A/C Heater Blower Motor. 10% OFF $75. Use Code: DIYSAVE10 Online Ship-to-Home Orders Only

What should I do if my GM fan won’t turn on?

Pull the negative battery cable and re-install, making sure it is very tight (also check the positive to make sure it is tight). See if this fixes the problem. Many of GM’s AC control heads have a built in reset feature that when power is removed and then applied it will go through a cycle that activates all the vent doors and mode doors.

What causes a blower fan to not work?

When this happens, you may notice that you will not feel anything blowing out of the vents at all. This may also cause the blower motor to work intermittently. A blower fan is connected to the negative battery terminal (also called ground) on one end and to the positive battery terminal through a blower motor resistor on the other end.

Why does my GMC Terrain blower not work?

For instance if the car is started on a middle fan speed, I can tell the blower is starting slowly due to the air flow, it may spin up a little, then down, then back up, back and forth a few times, then eventually landing on the proper fan speed and works flawlessly after that.

When did General Motors start making blower motor problems?

On General Motors vehicles built in the 2000 decade it’s not always an actuator problem. Therefore it will be necessary to perform some diagnosis. This is one scenario where the dealership has a diagnostic tool that can make quick work of pinpointing the root cause.

Why does my car blower motor not shut off?

If you have a vehicle with climate control system and a variable speed blower motor and the blower motor won’t shut off and stays on HIGH with the car turned off and the key out, chances are the blower motor motor control processor is toast or the HVAC control module is damaged.

How can I Make my Chevy heater blower fan work?

You have a fan resistence it should work in high speed only or not at all check all fuses to be sure you should have a 30 amp for the motor and is the motor new or used try the motor at the battery first to see if working before going further You can’t post conmments that contain an email address.

What are the symptoms of a worn out blower motor?

One of the symptoms of a worn out blower motor is that it can intermittently produce a loud screeching noise when running. How to test a blower motor? If the blower motor doesn’t work at all, the blower motor itself must be tested first. Typically it’s done by measuring the voltage at the blower motor connector when it’s turned on.

Is the blower motor on a Chevy Silverado working?

Blower Motor does not work on 1 and 2 speed chevy silverado – YouTube I had a Bad Relay. I got one here https://amzn.to/2PSr6fQ It seems the 88-94Trucks have a different system to control the speeds than the 96-00 OBS style Ch…

What are the symptoms of a bad blower motor relay?

3. Melted relay. Another more serious symptom of a problem with the blower motor relay is a burned or melted relay. Relays are exposed to high current loads and can sometimes get hot when they develop problems.

Where can I get a new blower motor resistor?

I replaced the blower motor resistor and the control unit with new parts from rockauto (ACDelco). I’ve checked the fuse in the dash fuse panel and it is good.

When do you Know It is time to replace your blower motor?

If you notice your blower motor is not functioning on certain speed settings, has a burning plastic smell, or the blower continues to run with the ignition in the off position, it may be time to replace your blower motor. Here are some steps you can take to confirm whether or not this replacement is necessary.

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