No Power to Radio or Heat control panel

[shooter1951]

HELP!! I have lost power to our A/C and Radio and am hoping someone on the forum recognizes the problem. We are new to the Vette scene (only 2 years). We took our 91 ZR1 out about 3 weeks ago for the first time this year and after about 3 miles thought we smelled wires burning. I pulled over and checked under the hood and dash but couldn't find the source. It seemed like it could've been coming around the glovebox but not certain. As soon as I shut the car off it disappeared. The A/C and Radio was on when it happened but when I restarted the car neither worked. In fact nothing in the heat control panel works. Before we smelled the "wires" I was trying to adjust the speakers but couldn't get them all to work. I checked the fuse box and all the fuses okay. Are there fuses elsewhere besides in the main box beside glovebox? Any help is appreciated. Thanks, Henry

[tccrab]

There's a secondary fuse panel up under the hush panel on the passenger side, but it doesn't have any fuses for the dash. It has fuses for the Airbag, power door locks, horn relay & electric fuel pumps.

Do you have interior lights?
If no, check the CTSY fuse, main fuse block, upper left hand side.
It supplies power to the Heater and the Bose amp.

Do the power seats work?
If not, check the PWR ACCY 30A circuit breaker, it's the black cube on the right hand side in the main fuse block.

If it isn't in the fuse block, then there's only a couple of other faults that could cause both the heater/AC and the radio to quit.
One fault could be the power lead to the either system has melted or has been rubbed through and shorted out, taking out both systems, leaving all the others OK.
The other fault could be a ground problem.

At the very least you'll have to tear the dash apart to get at, and into, the wiring harness. You'll need a volt meter, a test light, and a wiring diagram, plus lots of patience.
Remove the power from both the radio and the heater, and start looking for where the power stops.
This one could be quite a bear for an inexperienced person.
Electrical problems tend to be some of the most difficult and more expensive kinds of automotive repair.
You might get lucky and find a crisped wire right of the bat, and it might also be deep inside a large wiring harness that you might never find.
Only Murphy knows for sure.

Good luck!

TomC
'90ZR1 #792

[shooter1951]

There's a secondary fuse panel up under the hush panel on the passenger side, but it doesn't have any fuses for the dash. It has fuses for the Airbag, power door locks, horn relay & electric fuel pumps.

Do you have interior lights?
If no, check the CTSY fuse, main fuse block, upper left hand side.
It supplies power to the Heater and the Bose amp.

Do the power seats work?
If not, check the PWR ACCY 30A circuit breaker, it's the black cube on the right hand side in the main fuse block.

If it isn't in the fuse block, then there's only a couple of other faults that could cause both the heater/AC and the radio to quit.
One fault could be the power lead to the either system has melted or has been rubbed through and shorted out, taking out both systems, leaving all the others OK.
The other fault could be a ground problem.

At the very least you'll have to tear the dash apart to get at, and into, the wiring harness. You'll need a volt meter, a test light, and a wiring diagram, plus lots of patience.
Remove the power from both the radio and the heater, and start looking for where the power stops.
This one could be quite a bear for an inexperienced person.
Electrical problems tend to be some of the most difficult and more expensive kinds of automotive repair.
You might get lucky and find a crisped wire right of the bat, and it might also be deep inside a large wiring harness that you might never find.
Only Murphy knows for sure.

Good luck!

TomC
'90ZR1 #792
Thanks Tom,
Thank you for your response. I did check some of the spots you mentioned, seats, visor lights, windows, seem to work fine. While checking power in fuse panel my tester also quit working so I will finish that today. I am somewhat handy with electrical having wired a couple houses. However at 54 standing on my head under the dash is somewhat challenging so I will check some of the "easier" spots you mentioned. If I don't find the problem I'll turn it over to a "professional" to check the other spots you mentioned. Thanks again for your response, in the short time we've had our Corvettes the forums have been the most help. Anything you ever wanted to know about a Corvette can be found on the forums. When I find the problem I'll post it in case someone else has the same problem. Take care and Happy Vetting. Henry :cheers:

[shooter1951]

Tom,
I feel pretty stupid about now :redface: (and also lucky). I rechecked the CTSY fuse and it was blown. I don't know how I missed it the other day but I did. I replaced it and drove it for awhile turning everything on and off several times with no problems. Everything seems to be working okay, I don't know what the burnt wire smell was but I'll keep an eye on it. Thanks for your list, now I know where to look if it happens again. Take care and Happy Vetting, Henry (Shooter1951):handshak:

[tccrab]

Tom,
I feel pretty stupid about now :redface: (and also lucky). I rechecked the CTSY fuse and it was blown. I don't know how I missed it the other day but I did. I replaced it and drove it for awhile turning everything on and off several times with no problems. Everything seems to be working okay, I don't know what the burnt wire smell was but I'll keep an eye on it. Thanks for your list, now I know where to look if it happens again. Take care and Happy Vetting, Henry (Shooter1951):handshak:

Henry:
:cheers: =D>
GREAT NEWS!

Glad to hear that you got it figured out.

Of course, don't get too confident, Murphy always has the last laugh.
SOMETHING caused it to blow.
It might come back to haunt you, and it might not.
Be sure to keep a spare fuse handy.

Happy 'Vetting
Here's waving to ya!
:hello:

TomC
'90ZR1 #792