Topic: Help: Alpine Head Unit Issues

[RedBimmer93]

Hey Guys. I was helping a buddy of mine install an alpine head unit in his truck, and now we are having a strange issue. The screen works, but none of the other LED lighting for the radio controls are working. I am wondering if you guys might have an idea of what might be causing this. My mind will not be at ease until I find out what's going on :/

The story is my buddy has an alpine head unit installed in his old truck. One day somebody broke into his truck and stole the removable faceplate off his head unit. He then went out and bought the same head unit again so he can pull the faceplate from it and install it in the stereo he already had.
Fast forward to last weekend, and me and my buddy are installing the 2nd head unit he had in his new truck. His plan was to swap the faceplate back and fourth from vehicle to vehicle, to whichever one he was driving.

We wire everything up, hook up the head unit and test it out. After a little trial and error, the deck was working perfectly, no issues at all. It wasn't until we just finished putting everything back together when this issue popped up. Everything in the head unit works fine: the screen works and all the controls work, but the led lights behind all the controls are dead. Playing with the dimmer settings on the head unit doesn't do a thing.
Needless to say we are a little bummed about this. 

We did try switching the faceplate to the head unit in his old truck. It works perfectly in there.

Any ideas what can be going on? Is it possible that something is screwed up in the wiring that we can fix, or did we fry the head unit?

[LilDrunkenSmurf]

Did you wire up the dimmer signal wire from the deck? Maybe try disconnecting it?

[Canuckrz]

Break in the illumination wire in the harness somewhere.

[RedBimmer93]

Thanks guys. We did hook up the orange orange wire. After we found the issue, we cut the wires we soldered together and re-soldered them.

I suppose we could try disconnecting it, see what happens.


Might also be worth noting that there is one tiny spec of red light coming from one of the areas on the faceplate, outside of the screen. Id share a picture if i had one. Does this mean anything?

[Jay89]

Double check the wiring before condemning the headunit

[darthekai]

my money is on the illumination wire somewhere.
play with the dimmer switch ON THE CAR DASH too and also the headlights and try fully disconnecting the illumination wire from the head unit as well as the dimmer wire. if nothing makes the red light come on and everything is properly wired (check with a multimeter the voltages at the harness where these two wires go into the head unit), the head unit must not be passing the signal through to the faceplate. visually inspect the connector (both male and female sides), try moistening the contacts with a little wd40 (if its not on warranty). if on warranty, send that itchbay back.

[RedBimmer93]

Thanks for the input everybody.
Buddy brought his truck over tonight, and we took another stab at the issue. We turned the headlights on and off numerous times, We tried disconnecting the dimmer wire, examined the solder connections, tested the connections for continuity through the wires from the vehicle itself before the wiring harness adaptor... We tried adjusting the display settings numerous times before, but for some reason by using a different button on the unit... it started working again!?! 

I feel like a huge goof, but it was a good learning experience


*locks*