I noticed the license plate light burned out the other night, after finally getting a chance to replace it today, I followed usual steps. I took bulbe out, filament burned as I supected. I R/R the bulb, then ops check.Bulb still out, heres what I have done or observed so far.

1. Rechecked connection even re installed new bulb the other way, ( a long shot I know but figured I had nothing to lose)

2. Still no light, I checked the Fuse. Fuse is NOT burned out, followed wiring as much as I could see, does NOT appear to be grounded out, and wiring looks like it is in the protective wrapping all the way through.

3. Kept new bulb in, replaced assembly and looked up the electrical schematic in my Haynes Manual. There is only two wires to the lamp so it must be further downline in the system.

4. All other lights work Back up, tail, turn signal, flashers etc... And work in normal sequence. The only thing I havent tried is Center BRAKE LAMP and brake lamps, thats because I had no assistant and it was daylight, so no reflection. I don't think that is a factor, but I am trying to rule out all possibilities.

Any ideas?? Anyone, anyone, anyone, Bueller...Bueller.....Bueller..... Bueller........ ANyone!!!!!!!!!!!

Thanks,

Steve.

 

Maybe try another lamp just to make sure the 'new' lamp isn't a dud. Also, you could try taking the lamp out and putting a multimeter on the socket and see if there is any power back there when it should be turned on.

As far as other tests, have you tried wiggling the lamp/socket to see if something is loose within the unit? As far a wiring, I would suspect that the tag light's wiring doesn't travel too far and might just be tied in somewhere near the rest of the rear lighting.

I know none of this stuff sounds sophisticated, but I've found them to be useful techniques when troubleshooting.

 

Follow up.

Today I went with more troubleshooting. Heres what I found, so far. 1. I tried the other bulb from the package, just as a long shot, I figured the chances are extremely remote that two bulbs in the same package are bad from stock. 2. I tried a voltage test no luck. 3. Checked wiring harness, fortunately wiring only goes just on the frame side of the aft crossmember then it connects with the rest of the harness. 4. Fuse is no factor.
5. As you were on #4 Hold a minute. I looked at schematic again, I was checking fuse box in cabin, there may be another fuse in the P.D.C. The cabin fuse box shows fuse for back up lights. Looking at the schematic again there may be a fuse in the P.D.C under the hood I need to check. Stand by I should know something in a few minutes.

 

NO LUCK!!! No fuses anything even remotely related to lamps in the back, the only one is backup lights, but already checked that. Autozone/Advance neither carry the socket and harness I need. Sounds like a Dealer Visit, but I just hope the length of the socket wiring and connector is all I need. I did try jiggling, the harness, even contact cleaner. Any last minute ideas?

 

O.K Gents. I need some help. Follow up.

1. R/R License plate bulb no luck.
2. Checked all fuses/relayseven remotely related to lighting. All good.
3. Checked continuity of pigtail connector (Socket and pigtail connection is good.)
4. Spliced wires from pigtail into next segment of wiring harness, just as a remote chance that the dead wire might be in the connectors themselves. No luck.

It appears that the next segment of wiring harness that if downstream of the pigtail the question and I have followed the haynes schematic but I am lost. The question is After the pigtail/connector/socket where is the next segment of harness, end? I may in fact need a harness but I am trying to figure out how far down I need it. Any ideas?

 

CASE CLOSED:

It took a few tries, and I blew a couple of fuses during the troubleshooting process but I think I got it. I realize this step is not in the Dealer service manual but I think I got it.

1. Cut connectors from the light socket.
2. Spliced wires into the tail lights. I just followed the color coding and got Black/Yellowand Black (Ground) I did accidentally ground out the wires a couple of times during the troubleshooting phase, but once I got the electrical tape and a good splice tucked away it was good, fuse good, lights work and works during proper sequence, (When tail lights are on..!) No further issues, cleaned up area, tucked away dead line capped off connectors and I guess for now, Case closed.