No Windows, radio, or wipers?!

[dre2kx]

Got the 2000 Denali and suddenly had trouble with windows, wipers and radio. Radio would shut off each time I pressed the window button (on any door) and comes back on when releasing the window button. Here are all the symptoms and behaviors:
- Radio now stays off
- Can press "recall" button to see the time display on radio.
- Interior and under hood fuses all good
- Wires under fuse box all look ok
- radio comes back on at some random time after driving
- Radio is killed if window button is pressed or Wiper is engaged
- Battery voltage looks good (near 14)

Any ideas? I'm not exactly an electrician but will buy whatever tools I need to diagnose. Otherwise I can't even drive in the rain!

 

[rolfsent]

Got the 2000 Denali and suddenly had trouble with windows, wipers and radio. Radio would shut off each time I pressed the window button (on any door) and comes back on when releasing the window button. Here are all the symptoms and behaviors:
- Radio now stays off
- Can press "recall" button to see the time display on radio.
- Interior and under hood fuses all good
- Wires under fuse box all look ok
- radio comes back on at some random time after driving
- Radio is killed if window button is pressed or Wiper is engaged
- Battery voltage looks good (near 14)

Any ideas? I'm not exactly an electrician but will buy whatever tools I need to diagnose. Otherwise I can't even drive in the rain!

Check fuses related to the radio, radio batt.
Nevermind, just saw you checked those. Start checking for bad grounds.

 

[dre2kx]

After sitting overnight, radio works again. I can kill it by hitting the window button or wipers. If I keep playing with it, radio goes dead again till it sits for hours. Was able to get it to turn back on a few times by pulling and replacing the BATT fuse under the hood while truck was running.

Another strange thing: If I turn the key back to accessory while the door is open, it gives two chimes and dies. But if I do this while the radio is working (before touching the window button), it'll chime the whole time.

I bought a multimeter and test light. I can only get the blue radio 15 fuse to light up, not the red one. Wiper fuse is also not lighting.

I find it odd that these two fuses just happened to be positioned directly above/below eachother...

---------- Post added at 06:22 PM ---------- Previous post was at 04:49 PM ----------

Maybe I've found the solution?

Pulled the radio out and found 2 COMPLETELY BARE wires that ran all the way back behind the dash. Anyone else's radio like this???

 

[Gzes]

There should be no bare wires. Tape or replace them and see what happens

 

[SunlitComet]

man you electrical system is jacked. love working on it tho.

 

[dre2kx]

@Sunlit: Always feared the electrical in the past but now I'm going head first...
The good: Frayed wires behind radio are now taped up and the frayed stopped at the harness before going to where they may have touched the body.

Radio's working now so I put my new multimeter to it and all fuses except the #17 radio fuse read 12-13 volts. #17 constantly fluctuates between 4.9-5.3 while the radio's on. If I tap the window button, it instantly drops to 2 or 3 volts and slowly climbs its way back up and radio powers up again. If I keep playing with it, it goes back to it's not-working state at a consistent 1 volt. I took apart the dash all the way to removing the display gauges but no obvious issues are visible. BIIG thanks for any tips, help, or insight that can be provided.

 

[SunlitComet]

well the #17 fuse supplies the ignition trigger for the radio so when the volts drop enough it is thought as turnin the key off. can you probe the exposed terminals on fuses 11 &23 and tell me if you get the same voltage effect as #17 when doing your window switch thing.