dave1123

After fixing my left rear tail light C322 connector because the trailer adapter shorted out about a month ago, I'm driving down the road today, lit up a cigarette, then smelled something funny. Looking in the back seat, there was a haze of smoke! I pulled over quickly, opened the hatch, and pulled the side panel back off because I hadn't secured it yet, and there was flame coming from another connector in the same location! I pulled the harness out, big spark, and the flame went out. There's a couple of wires burnt off, but the lights still work, at least those I could check. I jammed my snow brush on the brake pedal and they work, tail lights and turn signals work. I drove it home and parked it until I can get a cup of coffee and contemplate my navel for awhile. The interesting thing is when you hit the brake, the clock and odo lights go out, then come back on when you release the brake. Huh.....

It's actually 42* out today and the rain quit, so now's a good time to look at it, but I'm not quite feeling it yet. Freaking Cherokee! I haven't had as much trouble with my WJ in the 6 years I've owned it as far as the electrics are concerned.

dave1123

I just spent about 3 hours going thru my FSM and Haynes circuit diagrams and can't seem to find what goes thru the C327 connector besides the rear hatch switch and a couple sensing circuits. There's a lighting circuit that goes to the trailer module that isn't there anymore. I just looked outside and it's dark! Oh well, tomorrow's another day. That Irish coffee didn't help either.

As far as the connector is concerned, it's toast. I'll probably just splice the wires back together again, AFTER I see where the short came from. Electrical diagnosis isn't that hard, but it IS time consuming! The circuits involved here are G78, L77, V13, V23, and V20. I really wish they could be more specific as to function, but you've got to pour thru the diagrams to find what they're for. All the wires are now black and I've got the cut back the harness cover to find the actual color codes. I think I can still figure them out by the connector cavities they were in, but it just increases the time.

Turbo X_J

Sounds like a major ground issue, the trailer adapter was probably the path of least resistance. The fact that the instrument lamps go out could be the dash ground is not making a good connection.

dave1123

Yeah, my thought exactly. A couple of nights ago, the liftgate warning light was glowing ever so slightly. That wire goes thru the C327 connector.

dave1123

Okay, I did a halfassed check of the C327 connector. With my digital voltmeter, I grounded one probe, then used the red probe to scratch thru the black plastic globs in the connector. I get nothing with the ignition off and the lights off. With the parking lights on, I get 4 to 5 volts and the high stoplight is on dim like a normal tail light and all the other lights work normally. When I depress the brake pedal, the high stoplight comes on bright and the regular brake lights work normally. If I hit the brakes with the parking lights off, the clock and odo lights go dim like the headlights are on. The liftgate warning light doesn't work at all. IDK if this is normal, but ever since buying the jeep, if you open the hatch at night, the cargo light doesn't come on, but does when you open a door. Since all the exterior lights work and nothing's burning or overheating, I'm going to drive it tonight for my papers and see what happens.

Interestingly enough, this crap happened the morning after I drove the XJ at 70 mph for about 20 miles, then parked it. It may not have anything to do with it, but it's interesting.

djgrayxj

Note from DJ
Dave your profile only list that you have a 2000 Grand Cherokee.
What is the year of the Cherokee that you are having problems with?
You need to update your profile to include the Cherokee.

dave1123

It's listed in my signature panel under the message. I could double-space it, but I ran out of room! Wait! I'll try that.

dave1123

Yeah! That worked.

boxburn

When you sorted out your C322 connector did any of the wiring look bad? Other than a direct short to ground it could be possible that you have some corroded/dirty wiring creating a high resistance.

From my experience with my cargo light, does the push button on the thing still work? My one was melted and was not allowing the boot switch signal to run through to the interior light circuit. I ended up soldering the wires either side of the switch together. The outcome is that I cannot turn the lights off if the boot is open however I don't see this as much of an issue as I don't leave it open for long periods of time.

dave1123

I really haven't looked at it yet. The one in my WJ, you just press on the lens to control it. The one time I tried that on the XJ, it didn't move at all. I just opened a rear door, then it came on.

boxburn

I don't have a lens on mine, it was only due to a scrap yard Jeep that I even have the light bulb. I don't know if it's common or used to be but no-one I've asked including the auto-elec next door has ever seen a bulb like it. However, maybe it's the same thing then. The 2 Cherokee's I've seen in a scrap yard both had that button melted. I was routing through all my boot wiring and expecting a broken wire where it bends between the boot and body. It took me a while to work it out.

BlackXJay

BlackXJay

Same exact thing happened to me in 2016. Once I cleaned up the grounds I never had a problem again. Weird how a ground in the cargo area was related to the radio

boxburn

I'd say in your case, the bad ground at the rear meant the brake lights found it easier to run back through the bulb, through the side light system and to the front of the car causing the light dimming issue.

BlackXJay

thank you for that