Easy lifehacks

Why does my GMC heater not work on high?

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.

Why does my GMC k1500 blower not work?

Here is a possible solution for your 1995 GMC K1500 blower that wont work on high. First remove the glove box and set it aside. Now look into the area that the glove box resided. You will see a wire harness covered in factory foam and next to this on the right you will see a flat silver box that is your ECM.

What causes a GMC CK HVAC unit to malfunction?

This is caused by an open Switched +12V power transistor, or it could possibly be caused by a defective blower speed switch. This is caused by a shorted Switched +12V power transistor, or it could possibly be caused by a defective blower speed switch.

Why is my HVAC not working on my Sierra truck?

The HVAC control head on some 1990-93 model year C/K trucks may not illuminate when the vehicle is first started. This condition is much more likely to occur after a battery disconnect or control head replacement but may occur after any ignition cycle.

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.

How to repair GMC CK Series truck HVAC unit?

Use paper clips or wires to jumper across the switch connectors on the wire harness. Key on engine off, compressor clutch should “click”. If no click, check the wiring harness for open wires, functioning high pressure switch, and correct voltages. TESTING LOW PRESSURE SWITCH. With the truck running, A/C turned on.

Here is a possible solution for your 1995 GMC K1500 blower that wont work on high. First remove the glove box and set it aside. Now look into the area that the glove box resided. You will see a wire harness covered in factory foam and next to this on the right you will see a flat silver box that is your ECM.

What is the temperature control on a GMC CK truck?

Power is routed back out to Pin 7 through a 3.8 ohm resistor and the Max AC switch, but on a 1500 truck Pin 7 is not used. The Blend (temperature) door control is powered directly from +12V via Pin 5.

Why does my Chevy blower motor not work?

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… 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…

How do you turn on a high speed fan?

Now put the zip tie between the red and black wires with the connector back together. Now pull the zip tie tight and cut the long end off with side cutters. Now reconnect your battery and turn your ignition switch back on and fan speed switch on high.

What causes a blower fan to turn faster?

The lower the resistance of the selected resistor in the pack, the higher the current that flows through the blower fan causing the fan to turn faster. The statements expressed above are only for informational purposes and should be independently verified.

How do you turn on a high speed heater fan?

Now pull the zip tie tight and cut the long end off with side cutters. Now reconnect your battery and turn your ignition switch back on and fan speed switch on high. The fan should be blowing on high, now wiggle the connector one more time the fan should stay on without interruption.

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 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.

Now pull the zip tie tight and cut the long end off with side cutters. Now reconnect your battery and turn your ignition switch back on and fan speed switch on high. The fan should be blowing on high, now wiggle the connector one more time the fan should stay on without interruption.

Why does my AC fan only work on high?

If your speed selector for your AC or Heat only works on high, or low, or if its missing any particular speed, this video will show you how to fix it once and for all. This is a fix for 2nd generation Dodge Rams (1994-2001-2002 2500/3500) Loading…

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.

What kind of blower does a 99 Silverado have?

I suspect the blower resistor which I just bought at the dealership. My ’99 Silverado looks like a ’98 and has the 5.0 V8 so I wondered if the place I bought it had it advertised wrong. I found out mine is the ‘Carryover model’.

Where can I find the heater switch on my car?

The older your car is, the easier this job will be. Most of the time, the switch is accessed from the back of the dash panel and can only be reached by removing a few pieces of trim. Cardboard panels held on by plastic pins or screws cover the bottom of the dashboard and are easily removed.

When to replace a heater blower motor switch or relay?

When the motor gets old and tired it will draw more current through the wires than a new motor. It may still draw enough current to blow the fuse after it runs for a while. In that case, a motor replacement is in order. Step 1: Disconnect the battery. Put on your safety glasses and disconnect the battery at the negative cable.

Why does my Chevy 1500 have no heat?

I have no heat only cold air coming through the vents changed thermostat still no heat. Heater core is flowing and heating up but still only cold air. I’ve seen people are talking about doors not opening to let air pass through the core.

What kind of engine did Chevy have in 1997?

Chevy placed a vortex or mini tornado within the combustion chamber to efficiently blend gas and air together. Vortec engines are the base engine used in all Chevy cars and trucks and come in a variety of horsepower and torque ratings. During 1997 Chevy still had a big block engine, the 454 cubic inch.

Why does my GMC P / you compressor not turn on?

No. Theres a schrader valve to prevent freon from escaping when you replace the switch. Just make sure you dont overtighten it. This is on a 2004 gmc p/u I have checked the fuse and relay all good. I have jumped high pressure switch .I have no power going to the high pressure switch wiring is good.

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.

I suspect the blower resistor which I just bought at the dealership. My ’99 Silverado looks like a ’98 and has the 5.0 V8 so I wondered if the place I bought it had it advertised wrong. I found out mine is the ‘Carryover model’.

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.

Where to check the blower motor relay on a Chevy?

Thankfully, it is fairly simple to tell if the relay is malfunctioning and to install a replacement. The blower motor relay is located in the under hood power distribution center and is simply labeled “Blower.” It will only take a few minutes to inspect and replace the relay if necessary. Open the hood of your Chevrolet vehicle.

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).

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).

Thankfully, it is fairly simple to tell if the relay is malfunctioning and to install a replacement. The blower motor relay is located in the under hood power distribution center and is simply labeled “Blower.” It will only take a few minutes to inspect and replace the relay if necessary. Open the hood of your Chevrolet vehicle.

Why is my heater blower motor not working?

Next disconnect the connector and look into the female side of the connector the red wire will show signs of it being loose, meaning that it looks like it has melted, This is due to a loose connection. Now if you opt to get a new GM connector or you can tighten the female connector so that the pin will fit snugly into it once again.

Why is my blower not working on my GMC Sierra?

When you switch to high,the blower motor relay coil circuit is grounded and voltage is now applied directly through the relay to the blower motor; bypassing the resistors. So, I would look to see if the relay is ok. It is a five terminal relay.

Why is my blower not working in Hi ( 5 )?

The usual failure of the resistor pack is if it works in HI (5) but not in any other mode or just a few modes. When you switch to high,the blower motor relay coil circuit is grounded and voltage is now applied directly through the relay to the blower motor; bypassing the resistors. So, I would look to see if the relay is ok.

Where are the vents on my GMC Sierra?

No output on dash face vents or defrost vents but floor works ok. I have tried the pulling the fuses both under hood and left of dash but that did not fix my problem.

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Ruth Doyle