Yes, I know there are many other threads about this, and I have used some of them to get my hatch lights working... sort of.

Upon inspection I discovered the little plastic plunger/spring/switch on the bottom of the lower hatch receiver had broken. So I fashioned a replacement out of some spare plastic model parts. (BTW, is there a source for a replacement of that little plastic plunger switch thingy?) Now the hatch lights turn on and off with opening the hatch or the doors.

But, the rest of the interior lights do not come on when just the hatch is opened. I think from what I have read that opening the hatch should turn on all interior lights.

So, TLDR, open door, all interior lights come as should. Open hatch, hatch/overhead lights come on, but not the doors.. Any ideas on what to check next?

 

NOTE first thing disconnect the hatch pin switch and leave it disconnected, this will disable the circuit ,
NOTE when the pin switches are activated they run a relay and the two door edge lamps and the interior lamps.

With the hatch open , this can kill the battery after a few hours,
so a tailgating party could result in a no start.

 

I should disconnect the hatch switch even though no lights are on when the hatch and doors are closed?

 

yes the door edge lights are on and you wont see them ,with a good hatch pin switch connected
You cant see the door lamps on, unless you roll the windows down to see them on with the doors closed .

NOTE the door edge lamps have to be working,
also a relay will be energized it will get pretty hot after the relay has been on for 5 mins.
I would suggest you get the 2 jetta lamps for the top above the mirror and the hatch top ,
put heat shrink on every connector.
I would also disconnect the rear hatch lamp and heat shrink the wires.
NOTE if the power wire to the lights gets to ground,
it will fry the harness all the way back to the CE panel and possibly take out the wires behind it.

 

Are you referring to the white interior lights on the door or the red ones in the jam. In my windowless garage at night, with the car closed up, there are no lights on visible anywhere. And the red lights I can see go off just as the door is about to close and pushes the switch.

 

The pin on the bottom of that assembly closes the ground circuit to turn on the lights. All the interior door and hatch lights have 3 wires on them. They all need to have the wired connected on them the exact same way as in one switch position you can manually actuate the individual light, in the opposite position, they all come on with any door or hatch is opened, and in the middle, they're off. If the wires aren't all looked up the same, the lights coming on when a door or the hatch is opened will never work right.

So start by taking all the lights loose from their installation spot to verify the 3 wires are on the same contacts in all of them.

 

This means that the switched current flows are working by design, at least up until your fixtures which are also switched. I assume your remaining interior lights illuminate when switched to the ON position?

 

roll the door windows down, close the doors,
then open the hatch and connect the hatch latch pin switch .

Look inside the window slots in the door ,
and you can see the backside of the door lamps,
the rear door edge lights should be on.
disconnect the pin switch to the hatch latch.
The lights should go off.
Since you have verified the lights are working its an easy tell tale to see if the circuit is energized.

Note Pete gave great info for the interior lights circuits,
the critical parts are the original lamp housings will melt and bend if the lights are left on for more than about 5 mins, with a good strong battery.
If you have a dark car the lamps will also melt if the car is left in the sun as the roof temps can get pretty hot.

NOTE the Jetta lamps are a nice upgrade to the roof lamps ,
you can only fit two of them one above the mirror and the other at the top of the hatch.
the aft hatch lamp opening will not accept the Jetta lamp as its not deep enough,
so that is why I suggested to just completely disconnect that lamp and heat shrink the wires.

NOTE a brittle lamp housing can inadvertently snap inside and the connector can break off the lamp,
this then can ground and smoke the entire light harness back to the CE panel.

NOTE this applies to all the roof lamps, and the aft hatch lamp.
its a pretty difficult job to repair as the RR quarter interior liner must be removed to replace the wires.

NOTE the wires at the top of the hatch are different colors so use your multi meter to test for power and ground and switched.
NOTE the significant part about the wire routing is that every lamp has 2 grounds, (a ground and a switched pin)
the brown ground wire goes to the lamp chassis pin,
then the brown/white switched wire goes to the other pin on the lamp,
then the isolated power connection.

NOTE the interior door floor well lamps are not critical for ground wire position,meaning the grounds can be wired either way since they are made from plastic.
the power connection must be isolated from the switch position

 

Awesome. Thanks for all the advice and tips. I have disconnected the hatch circuit for now and will order a few parts to upgrade and get back to it when they arrive.

 

As an alternative, you can put a 42mm festoon LED in the hatch lamp housing and it will not get hot nor will it drain your battery (if the rest of the cabin bulbs/door marker bulbs are also LEDs). I used a SuperbrightLEDs 4210-WWHP6-V2 (warm white color temp) in the stock rear Hella lamp housing (911 632 102 00 70). It looks like the incandescent bulb that it replaces but uses less energy and runs cooler. I've left my hatch open for longer than an hour. The bulb does get warm maybe 30C but not enough to melt the housing.

 

I have led bulbs in all my 928 interior light fixtures and the glovebox. Better light, less amperage draw, and less heat.

 

Yes, I have ordered some LED bulbs for all the interior fixtures and glovebox.

 

Please note that a relay is also activated when the interior lamp circuit is on,
it gets pretty warm after being on for 5 mins.
IDK what it will do with the LED lamps so more data points are needed.
That said if your working on the car and the lamps are on for more than 5 mins then I suggest to disconnect the battery.