I had my girlfriend swapping my dome lights to LED's and she says "while I was backing the screws out the dome light went off" and since then I haven't been able to get them to come back on. I tried swapping back to the regular bulbs and it didn't change a thing. I figured I would just deal with it and fix it later. I went to install LED's into my HVAC panel and realized I didn't have my torx wrench with me. So I reassembled everything and started the car and drove home. On my way back home I immediately noticed my aftermarket cd player and speedometer were nolonger working. I was instantly frustrated, when I got home I tore back into my dash to see if wires were messed up. I search for a good 30minutes and couldn't find anything wrong with my wiring. Then I went ahead & installed LED's into my gauge cluster, it went smoothly. I put it all back together and then I noticed that my tach nolonger worked... Now I noticed that my unlock/lock buttons, power mirrors, door chime, keyless entry, remote trunk release nolonger work. When I press the "unlock" button in the inside of the car my signal lights come on.

List of what isn't working:
Aftermarket cd player
Dome light/map lights
Speedometer
Tach
Unlock/lock buttons
Mirror buttons
Keyless entry
Remote trunk release
Door chime

I have no clue what's going on here, I just know everything worked perfectly up till an hour ago! Where do I start? I checked the fuses and they all came back to be fine. So what do I do now?! For reference I have a 1998 Mustang GT.

 

Under the hood right behind the battery is a fuse cluster.

And if not mistaken,.. those LED are only supposed to run off 3.4v not 12v. So unless you ran a regulator or they have one built in you may have created a short. Not good in a computer control car.

If it aint broke,.. dont f' with it.

Hurst

 

I already checked every single one of my fuses under the hood.

 

I found this thread that seemed to be my "saving grace": Speedometer, Dome light, and Radio Not Working NEED HELP!!! - Mustang Forums at StangNet

And then I found the interior fuse panel for my car:



Went out & tested all of them and only found #4 to be the only blown fuse. Anyone have any ideas?

 

If you've shorted it out through the dome light it should have just blown that fuse. If no other fuses are blown then you may have blown an inline fusible link within one of the main power feeds to either of the clusters.

Is your Alt still charging? Do the other gauges still function?

There is an inline fusible link for the center console. Its just ahead of your shifter down near where the head Mach460 amp should be. PITA to get to. Removing the shifter cover will not give you enough room,.. the entire console needs to come out to check it.

As for the speedo and tach,.. no clue. Those are on a different circuit and should not have been effected unless you blew out the VSS relay,.. and even that should not have effected the tach. Since both are out,.. my guess is you have a broken or shorted wire behind your cluster or one of the connections in the plugs where it slides in has failed to make contact and is/was dirty and now failing to make contact.

For future reference,...
Disconnect the battery anytime your messing with these kinds of things. Just pop off the ground terminal.


Hurst

 

Is there anyway to check to make sure that's exactly what it is before I go ripping into the dash? I got my tach working this morning, I guess I didn't have the connectors pushed together all the way or something. Thanks for your help.

 

Well I just learned my lesson about visibly inspecting fuses....

Both #6 & #8 looked just fine, I popped new ones in both of them and instantly the door chime and the radio popped on!

 

not sre if you got it working now but, the dome light in my 86 has a ground wire that has a fitting for one of the mounting screws. if you have the same yours might have shifted and is not making contact no more.