[Joem2254]

Ok. I'll try to remove it in the morning. Freezing and dark here now and have to work on it outside. I'll look online online for a video on removal. I really appreciate your help. Joe.

 

[Ryan Menke]

Have checked all fuses and swapped the relays under hood. Also checked for any codes. Is it possible that the blower relay also controls the blower for heat, air cond and the rear window wire defrost? I started the truck yesterday and turned on to defrost and nothing. Like there is no power at all to the dash controls for these things. All fuses are good even at the dashboard. I hadn't driven the truck in a week but I seem to remember a smell of burning but it was short and gone. If it's the relay that fried, would this also eliminate power to the rear window defrost? Thanks in advance for any help. Joe.

check blend door function

 

[Joem2254]

The blower and rear window defrost don't work at all. No power at dashboard unit, not even for the air cond. Nothing works at that control unit.

 

[Ryan Menke]

Trace the power wire for the dash all the way to to the fusible link? starter solonid!

 

[Joem2254]

Starter solenoid?.

 

[RayVoy]

Joe, your problem is with the circuitry of the dash unit.
I just reread the early post, and I'm going back to the one where you posted that when you disconnected the blower motor, the lights came on

That makes me think the dash ground(s) may not be a clean as they could be

I'd try a temporary ground. Run it from the battery neg to a good clean spot on the dash near the blower motor.

The other thing you could try is just a simple reboot, remove the neg battery cable for say 30 mins, or an hour.

 

[Joem2254]

Thanks Ray.. I added a 12g ground from the wngine block to the lug ground on the firewall. I read that the type of cable there can be an issue. I've had the battery disconnected earlier for several hours. I am wondering if the part below can fail completely and cause this issue? Since nothing in this panel works at all. I only see dash lights.

acdelco 15-74000 HVAC control panel

 

[RayVoy]

You may have reached the point where there is nothing left to do, but replace it.

Just had a thought through, a lot of codes don't turn on the CEL, you may have a code in memory that would point us in the right direction.
A lot of readers can't read these codes either, try a parts store, they should have high end readers that would see body codes.

 

[Joem2254]

I can read some codes. But their were none reported. I will try a local parts store I deal with. Thanks. I'll post whatever the results are.

 

[Will Mann]

I just started to take out the blower resistor but I really didn't think it was going to be the problem. I checked all fuses. Not exactly sure in the hood fuse box if there is a relay there. I did swap the ones I could to see if any thing changed.

It’s the blower resistor and harness. You should be able to get both parts on Amazon for about $27. What you smelled was the ground wire burning at the resistor. I had the same exact problem. You will see the burn marks when you pull the resistor. You probably smelled the burning more than once and thought it was coming from outside the truck.

 

[Joem2254]

Would this also cause the rear defrost to not work, no power? The resistor for this truck is dealer only and 175$.

 

[Joem2254]

I will pull the resistor as soon as I can. Snow and freezing rain here and have to rock on outside. Garage is full with a boat. Thank you

 

[Will Mann]

Would this also cause the rear defrost to not work, no power? The resistor for this truck is dealer only and 175$.

Look on Amazon, the two parts usually come together for around $27

Would this also cause the rear defrost to not work, no power? The resistor for this truck is dealer only and 175$.

Look on Amazon for blower resistor for your truck. it will probably look similar if not the same.

https://www.amazon.com/dp/B07M5WF9MT/ref=cm_sw_em_r_mt_dp_wGu.FbJBBYEGA?_encoding=UTF8&psc=1