Chevy express van air conditioning off and on

[KYMISTWALKER]

I have a 2014 Chevy express van 4.3 L, the air conditioning is cold and the blower motor is working, but when I’m driving it quits blowing air, it stays cold, but after a few seconds or minute, it will start blowing cold air again the fan I guess is switching on and off

 

[Wireman1987]

It’s either the hvac controller head with the selector knobs or a vacuum issue or both. We have express vans with the same issue and that’s what fleet shop tells us

 

[BobsArmory]

This is a long shot but my daughters car was having similar problems. Couldn't figure it out for the longest time then I replaced the battery because of slow crank and everything was fine. Low voltage must not have been playing well the HVAC

 

[KYMISTWALKER]

It’s toast, it just kicked the bucket no fan no air-conditioning no nothing coming on. I guess I gotta order one.

 

[KYMISTWALKER]

I have a Chevy express van the climate control panel has completely quit working nothing works, I bought one on Amazon a cheap one replaced it no luck, I went down to O’Reilly’s and bought a brand new AC Delco part replaced it no luck, I’m in a standstill, checked my resistor it works. Can anybody help?

It has a fully charged battery

 

[D60]

Stop throwing parts at it. You've gotta find inputs to that panel and see if it's even getting power -- or ground. If not, you have to trace that back -- is it fused? Or is it dependent upon BCM commands or some other module? Is it switched through the ignition switch?

But when you say "nothing works" what EXACTLY does that mean? Are you simply getting no blower? Without the blower it can be difficult to tell if vent position or even temp is changing.

Are you saying you have no blower, the air temp does not change when commanded, AND the vent positions do not shift? This seems unlikely if so.

 

[KYMISTWALKER]

I’m not getting anything no light no blower motor no air conditioning kicking on and off

 

[BobsArmory]

Pay a professional to diagnose and repair rather than playing Darts with Parts. I think you will be money ahead

 

[KYMISTWALKER]

Pay a professional to diagnose and repair rather than playing Darts with Parts. I think you will be money ahead

I got ASE Certified mechanic here working on it. That’s why we changed the climate control module. We thought it was it and then we checked the relay were at a standstill here.

 

[KYMISTWALKER]

Pay a professional to diagnose and repair rather than playing Darts with Parts. I think you will be money ahead

Define professional, what is a professional

 

[wander2039]

Is the Express’s HVAC vacuum controlled.. can’t remember and ours is at the property. I know my Dakotas is and it goes to defrost I can’t recall if I’ve ever had that happen on it.

 

[KYMISTWALKER]

Is the Express’s HVAC vacuum controlled.. can’t remember and ours is at the property. I know my Dakotas is and it goes to defrost I can’t recall if I’ve ever had that happen on it.

Yes, it’s got a vacuum line that comes down on the passenger side

 

[wander2039]

Yes, it’s got a vacuum line that comes down on the passenger side

Is it blowing air out the defrost vents when it stops working? I thought about it last night and only had issues with RV/Express 3500 platform when we were climbing the rockies. It such a rarity unlike it was on the Dakota don't think about it. If it's only putting air through the defrost vents could be vacuum related, not sure how you'd check it. I wouldn't count out the new part being bad either.

 

[KYMISTWALKER]

Is it blowing air out the defrost vents when it stops working? I thought about it last night and only had issues with RV/Express 3500 platform when we were climbing the rockies. It such a rarity unlike it was on the Dakota don't think about it. If it's only putting air through the defrost vents could be vacuum related, not sure how you'd check it. I wouldn't count out the new part being bad either.

It started the little light quit, which might not have nothing to do with it. You know when you turn your parking lights on, and then it started the air was working, and the blower motor was coming on and off, and it was blowing cold air, cold air condition is working , so the air was cold and it was blowing and then quit and then drive 2 miles to start blowing again and then it’s completely shut off

So the air conditioning was cold, but the blower motor was cycling on and off

I’m thinking it’s a ground or vacuum related. I’m looking at the diagram here with my mechanic he is ASE certified and he is a professional

 

[repairman54]

By the looks of the wear on control buttons its got a ton of miles on it. Blower brush's are probably worn out, common issue. Hit a bump or smack the blower fan motor and they come back on or go off. Check the blower resistor and its connector also.

 

[KYMISTWALKER]

By the looks of the wear on control buttons its got a ton of miles on it. Blower brush's are probably worn out, common issue. Hit a bump or smack the blower fan motor and they come back on or go off. Check the blower resistor and its connector also.

I’ve checked the resistor. It’s fine, shouldn’t having a new module remedy that though I put a brand new one in it actually two and it didn’t fix it HVAC module.

 

[mk378]

Blower brush's are probably worn out, common issue. Hit a bump or smack the blower fan motor and they come back on or go off.

Yes that is where I would start. A worn out motor will be intermittent for a while then quit entirely. The test is very simple. Turn on the key and set the fan speed dial to high and the mode switch to any position except off. Use a voltmeter to measure the voltage between the two wires (red wire and black wire from the resistor) at the blower motor plug-- while it is still plugged into the motor. If there is 12 volts present but the motor is not turning, the motor is bad.

If there is not 12 volts reaching the motor, I can write up some further troubleshooting to do with a voltmeter.

 

[repairman54]

I’ve checked the resistor. It’s fine, shouldn’t having a new module remedy that though I put a brand new one in it actually two and it didn’t fix it HVAC module.

Not if the blower brushes are worn out. Check for power to the motor itself, got power then it's the blower motor.

 

[D60]

Most blower motors are blindingly simple with a red and black wire. With it in hand (carefully 'cause it'll jump) jumper the wires. Hopefully it's obvious which polarity red and black gets (but it might just spin backwards the other way)! If it tries to take orbit, it's ok

I found a bent spindle on a new Motorcraft motor this way. When installed it was wobbly enough it couldn't spin. But then I found power at the connector so I removed the (NEW) motor and when bench testing it spun around like a tire recently balanced at Discount

 

[KYMISTWALKER]

Fixed it it was a little relay under the drivers seat. It stumped us.
I went ahead and put the new HVAC module is anyway