1999 LX - Head Unit Not Working and HVAC panel went dark (1 Viewer)

[OwnerCS]

I removed the trim around the radio to install a Ram mount. Since reinstalling it, the HVAC controls have gone dark. The HVAC unit still works, just the LED display has gone dark.

The radio no longer works. That may not be related to removing the trim panel. In checking the 1999 LX manual for fuses, my engine compartment fuse box doesn't seem to match the manual.

Is fuse 16 for the radio really under this hood?

 

[jLB]

On my 99 LX, the radio fuse is in the under hood fuse box, it’s the yellow 20 amp fuse in the front edge, passenger edge, corner.

 

[OwnerCS]

On my 99 LX, the radio fuse is in the under hood fuse box, it’s the yellow 20 amp fuse in the front edge, passenger edge, corner.

Thank you. The stereo fuse is good.

The HVAC controls (rear fan included) work. Just no button lights or display LED. If I recall, those were working last night.

 

[jLB]

I’d recheck that the “front panel” connectors are fully seated after installing your RAM mount. If that’s good, did a pin get bent, or pushed out of the connector?

 

[OwnerCS]

I’d recheck that the “front panel” connectors are fully seated after installing your RAM mount. If that’s good, did a pin get bent, or pushed out of the connector?

The pins and plugs all look to be ok. Everything was seated and clicked. There is a little red flashing light truck image for the alarm on the panel that still works. That the only thing on the panel that will light up.

 

[jLB]

I’m more familiar with the innards of our 2000 LC center stack, after replacing all of
the backlighting on my son’s. I haven’t had to do that on the 99 LX (yet).

 

[OwnerCS]

I’m more familiar with the innards of our 2000 LC center stack, after replacing all of
the backlighting on my son’s. I haven’t had to do that on the 99 LX (yet).

A few months ago, I had a chance to buy a three-knob LC HVAC center console control unit. I didn't get it because I was still running the stock radio that is larger. I should have bought it to keep on hand if the LX unit failed and I needed to change radios.

I planned to eventually change the radio. I didn't expect both to fail at the same time.

I do have a Nac stereo amp from a 2000 base model part out. I might try swapping the amp to see if it fixes the radio problem.

Strangely, the hazard switch and diff lock are both working. I think something just failed in the HVAC control unit that powers the button lights and LED display.

I'll put in a call to Tanin Electronics to see if they can check or repair the HVAC control.

Lots of local options for replacing the radio.

 

[jLB]

I remember something about power for the head unit going through the amplifier, from when we were looking at an “amp bypass” on my son’s 2000 LC, but that really wouldn’t explain the combination of AC display/lights, and the stereo going out at the same time.

What would those have in common.., Bad ground in that general area, maybe?

 

[OwnerCS]

I remember something about power for the head unit going through the amplifier, from when we were looking at an “amp bypass” on my son’s 2000 LC, but that really wouldn’t explain the combination of AC display/lights, and the stereo going out at the same time.

What would those have in common.., Bad ground in that general area, maybe?

Good point.

I'll go back and look for a loose ground. I may have knocked one loose when reinstalling the console trim cover from changing the shift handle and indicator plate.

Unfortunately, I didn't try the radio until after I discovered the HVAC display stopped working. I can't say with any certainty that those problems happened at the same time. It was just discovered at the same time.

I remember a nightmare with my kid's F150 when trying to remove a premium sound amplifier that was under the seat. A stereo installer had bypassed it. Though some of the dash controls ran through it. Seems like it did more than just amplify the stereo.

 

[OwnerCS]

Swapped out the amp with a known working unit of the same part number. I did shake out some coins from the old amp. No luck.