jbrob007

I have an 86.5 S3 with a (you guessed it) interior light & rear hatch issue. I've read every interior light & rear hatch thread there is... and theres a BUNCH, but I probably missed something... I still have two issues - interior lights (door open mode) will only work when the rear hatch is open. None work (door open mode) when the hatch is closed and a door is opened. Rear hatch release only cycles when the rear hatch is open.

What I've discovered so far: I've cleaned both door pins (per Dewayne's thread) and I can hear the relay activate when the pins are depressed so those work along with the relay.

I've taken out every light switch, I think the wiring is correct & its all tight with connections covered with elec tape, etc... No improper grounds that I can find.

I removed and cleaned the driver side door "little red caution light" and it is completely corroded and inop - I took it all out cleaned it up as best I could and put it back together - not enough wire to fix without taking apart the door panel (also need a new fixture). The passenger side door "little red caution light" was cleaned successfully but its still inop (might be caused by driver side door light issue).

ALL interior lights work in the "manual on" mode - no problems.

ALL interior lights work in the "door open" mode ONLY when the hatch is open & they ALL turn off when the hatch closes - I'm THINKING they are wired correctly?

The rear hatch motor cycles correctly but only with the hatch already OPEN. I've adjusted the motor up & down with no change. At least the hatch switch (under the releasing mechanisim) is operating correctly as it turns off all the interior lights when the hatch is closed. Theoretically, the car should recognize that the hatch is closed since the light switch is functioning correctly.

Questions:

1. Will the completely corroded drivers side door "little red caution light" effect the operation of the interior lights in door open mode? If not, I'm stumped...

2. Why does the rear hatch release cycle through ONLY when the rear hatch is open? When its closed it wont operate at all. Why is that? Would it work if I switched the wiring (+ / -) at the hatch release button?

Thanks in advance,

Joel

jbrob007

Bump.... 60 reads and no help.... HELP!!!

Shane

I haven't had to trouble shoot this yet, but what about the pin switch for the hatch, have you checked it?

WallyP

The brown/white wire that runs to each light must be grounded for the lights to burn in "door open" mode. It would seem that the brown/white wire is grounded only by the hatch switch.

Remove a door switch. The brown/white wire should be attached to the plunger. Solidly ground the wire to a good body ground - the lights should come on. If they do, the problem is in the grounding of or operation of the dooor switches. If not, the brown/white wire is disconnected somewhere between the lights and the door switches.

jbrob007

Shane, I think the rear door hatch switch is the pin switch - I'm probably not using the correct jargon. Its the switch located underneath the hatch release motor and yes it works. When the hatch is closed it extinguishes all the lights in door open mode.

Wally, I can hear the relay activate when I push in the door pin switches. The door chimes, etc, so I think they're working as designed. Thats why I'm stumped...

Alan

Replace the interior light relay - it dosn't work, your hatch sounds like it works just fine - just fix the interior lights

Given what you have said the door end light functionality has no impact on this...

Alan

jbrob007

Thanks Alan... Not what I WANT to hear (since those are like trying to find hens teeth & twice as expensive), but I'm glad to know whats wrong so I can fix it.

Would the faulty relay also be the reason the rear hatch release only cycles when the hatch is open?

Thanks!

Joel

jbrob007

You must've edited that while I was typing... I'll order the relay if I can find it from one of the big three

Anyway, the hatch release works (I guess) but only when the hatch is already open. It wont cycle, nothing, when the hatch is closed. Open the hatch and pull the release button and it cycles. I dont get it - what am I missing?

Alan

The hatch operates the interior lights & so do the door switches when they work correctly.

The hatch release is designed to only work when the doors are open (safety interlock)... it does this by initiating an opening cycle only when the interior lights are switched on by the doors (also incidentally by the hatch).

You only have the incidental part right now...

Alan

jbrob007

Ohhhhhhhh.... now that makes perfect sense - the release system recongnizes the hatch is open so it cycles the motor. BUT, when the hatch is closed it doesnt recognize a door is open because the relay is faulty - hence no interior lights & no hatch release. I would have stumbled upon the fix when I replaced the interior light relay, but wouldnt have known WHY it was fixed. I'll pass this info on to my local club members as I'm sure I'm not the only one with this issue.

One more thing to mark off the "To Do" list! Thanks a million for your time & expertise! I owe you a beer (at least)

Joel

WallyP

Since the relay doesn't work now, you have nothing to lose by opening it and carefully checking the contacts and wiring inside...

Alan

Agreed - always worth a try - nothing to loose...

Alan

jbrob007

Guys... I can turn a wrench... clean parts... replace parts... trouble-shoot various things and I can cook like no one you've ever met, but I'd have NO IDEA what I'm even looking at inside a relay. Although, there are a couple of guys in my club that might... I'll let 'em have a go with it - maybe its salvagable

Thanks again for all the help! I love this place...

Jchiodi

dont know about this particular relay, but most are similar. I know from working on volvos that bosche had a problem during the 80's with their relay soldering. Think they went to a new process, automated it, and problems started popping up years later.

Resoldering the posts is fairly simple, especially if you got one on order! Should be just 4 plugs, i think, run a fine tipped soldering gun on them till solder flows.

Jc

993turbo

Just fixed the same problem today on my 90' GT. It was the interior light relay. Changed the relay, problem solved. :-)