Hi folks, here's a dumb one for y'all.

So, while I was working on my bose center amp refurb, it was the first time I had the glove box out and noticed the fact that, hey, I'm supposed to have a light that turns on when the glove box is opened. Never noticed that in the nine years I've owned the car.

I checked the bulb, and there's continuity across it. I checked continuity across the switch, and the switch works in both positions. I'm not getting any voltage at the wires leading to/from the switch, though, not with the key out or with the key in ACC or ON.

Any suggestions? Thanks in advance!

edit: I checked this wiring diagram and it appears that the glove box light goes to a module called "CPU1" (in the process of researching things, I came across this scary thread about CPU2, not looking forward to having to investigate that!). I assume CPU1 is down in the driver-side footwell, right?

 

I believe it is attached to the back of the footwell fusebox. Rare thing, issues never seem to come up with it.

 

Have you checked if the glove box light works when the head lights or parking lights are switched ON? Try that first - if that worked, then you're done troubleshooting! Per the wiring diagram, turning the head/parking lights on is a prerequisite to energizing the TNS relay, which in turn sends power to the glove box light circuit. Since you didn't say your headlights aren't working, I'm going to assume that part of the circuit is fine, and advise accordingly.

None of the CPU1 or CPU2 boxes are involved here. The glove box light and its switch gets its +12V power via the TNS relay, but the path goes thru a bunch of connectors/junctions before it gets to the glove box switch. Here's the two relevant FSM wiring schematics ('93 USDM edition FSM here):




On the right hand side, you can see the glove box switch & bulb wired in series to ground, with note indicating power is coming from elsewhere - TNS relay, section E3


And here is section E-3, with the TNS relay wiring, I highlighted the current path to the glove box circuit in yellow....


So here's how I would troubleshoot this - start with the tested good glove box bulb installed in its socket (since you already tested the bulb & switch individually)
1. Verify that you have continuity from the R/B wire (I3-09) terminal of the light socket to ground (any chassis metal point will do) with the glove box door OPEN (which closes the switch).
2. IF you have continuity in step 1, that means you're not getting power from the TNS relay, so with the head/parking lights switch ON, use your voltmeter to check for +12V power at all junction points along the highlighted yellow path in the above E-3 schematic. NOTE: If any of the other lights indicated in that E-3 schematic are working with the head/parking light switch ON, then the TNS relay itself is good.

 

Uhh.. yeah... I'm uhhh just gonna exit stage left right now....

I guess I should've studied more of the diagrams, I just found this one online and it just said "it goes to CPU#1" and I left it at that. Goes to show how a little knowledge can be a bad thing!



So yeah, thank you VERY much for your help. I turned the light switch and the glove box light turned on immediately.