I have exhausted all front-line resources and now I lean on the members here for direction...

Radio has no power - Clock works
Leading up to this point the radio was always woozy, power flickered in & out. All interior lights work except the dome light which I found has no bulb. Both the cig lighter & power port work...

Installed aftermarket radio wiring harness adapter, connected test HU, No power at all... Yellow 12v hot at all time wire is dead af! 0v.

Pulled & Tested w/ MM Fuse # 8 (10A) & Fuse # 12 (10A in blk clip) both show 0 resistance. Did the same for a few under the hood, same 0 resistance.

Connected everything back in it's OEM fashion.. back to sq1.

 

If the yellow wire is supposed to have 12VDC, and you have 12VDC at the fuse box, there is a break in the yellow wire between the fuse and the dash. You'll just have to trace the yellow wire back until you find the break. Alternatively, if you know you have good 12VDC coming off the fuse box, you can just run a new wire from there to the back of the radio, bypassing the break. No idea if anything else is driven off the same wire though.

The symptoms do indicate that you were wearing a hole through the wire somewhere, and I'm surprised that the fuse didn't pop so it appears that the break was not caused by grounded metal.

 

I don't have a book for a 97, but I want to say the 12V constant hot comes from the dash-side distribution block?

This is from the 01 manual, take with grain of salt

Fused B+ constant
20 gauge pink

Goes to pin 3 of Connector 8 of the dash-side junction block

Goes to Fuse #1, 15 amp (shared by SKIM, cluster, Radio, dome, cargo lamps, glove box lamp)

Goes to Fuse #7, 40 amp of the underhood power distribution center

 

I've ripped the lower dash apart, unraveled the blk tape all the way up to the mesh loom where it becomes unreachable/non-removable... no visible breaks to the OEM harness pink wire / Aftermarket harness yellow wire labeled Battery Constant.

Since the radio appears to be powered by both F#12 & F#8 how do I test for 12v coming from those Fuse Panel locations with the fuses installed?

And if the radio gets no power, how TH does the clock work? It's one unit...

 

Great question. I'm not sure which of the 2 wires carries the operating current load.

 

My Haynes manual leads me to F#12 however with the door open and all interior lights on when F#12 is pulled the lights go out, and come back on with fuse pushed back in...

Might be time to "add-a-circuit" and tap a fuse if this pink wire is preventing me from having tunes. I also don't want to start a fire if there's a live potentially broken 12v wire i can't see

 

it's possible the wire may have fallen out of it's connector at the dash-side fuse block. It's a pain to get to that side of it, though. You can barely see it if you look up from the emergency brake pedal.

 

I couldn't see a thing! Nearly broke my neck trying lol.

YOU WERE SPOT ON!

Went out for more testing. Brought out the test light, probed F#12 and got power. went as HIGH as possible on the pink wire, pierced it w/ a safety pin and found power! So the break isn't visible, no bare spots in the wire insulation. I'm going to repeat coming down the wire so I only cut what's needed.

Know how I remove the PIN from the connector so I can PIN the spliced wire into the OEM connector?

 

I think the factory connector is a molex-type, but i don't recall and i don't have a harness kit handy to look.

The pin has a 'tang' that sticks out and catches on the plastic housing. normally you push something (like your safety pin) in from the connector side (not the wire side), it depresses that tang, then you can pull the wire and pin back.

 

Well my pops reminded me of the clamshell snap type connectors which allow you to tap the bad wire, and run a new wire along it's side. I happened to have 2 laying around so I ran a new wire along side the bad one. I did it as professionally as I could. I used wireloom to isolate the repair and etape at each end concealing the connectors. Tested for power at the OEM PIN's for 12v con & 12v Ign both passed! Connected OEM Stereo = Same no power condition. Removed. Deemed radio DOA from me neglecting this matter before now...

Connected aftermarket wire harness, Now seeing 12v @ yellow wire. Wired up test HU, unit fully operational! Installed all dash parts and tested in both Run & Acc conditions with success!

THANK YOU ALL!