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Discussion Starter · #1 ·
I know, I KNOW!

This has everything to be just another door lock issue but this kinda confused me. Since this Sunday, whenever I open the driver's door, none of the interior lights will come up but the puddle light will :confused:

I thought both of these lights (puddle + interior lights) got their signal from the same micro switch, so how come just the puddle light is turning on when I open the door? If the puddle lights "knows" the door is opened, how come the interior lights don't?

This really SUCKS, it's been something like months when I had my door cards and locks completely teared apart and overhauled, don't get why it would happen so soon. VCDS shows no error codes at all. :confused::banghead:
 

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...and you're 100 percent certain that the OH console 3-way switch is in the correct position for the interior lights to come on with any of the doors open?

If so, the only other possibilities are a blown out bulb or a wiring issue between the OH light and the CCM. Time to break out that multi-meter...

Good Luck :beer:
 

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Discussion Starter · #3 ·
...and you're 100 percent certain that the OH console 3-way switch is in the correct position for the interior lights to come on with any of the doors open?
Yes! Because when I open any of the other doors the main light will come up :(

If so, the only other possibilities are a blown out bulb or a wiring issue between the OH light and the CCM. Time to break out that multi-meter...

Good Luck :beer:
Oh no :(
 

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The puddle light gets its signal directly from the microswitch in the door lock module, while the interior lights (and the door open indication on the dash) get the signal via Canbus. Specifically, the door lock module is wired to the window controller, which has the Canbus node built-in. It puts the switch status on the Comfort Canbus network where it is read by the CCM (to turn the interior lights on) and the instrument cluster (to indicate "door open" and to pass it on to the ECM so it can prime the fuel).

Can you control the other windows and locks from the driver door? If not, the Canbus to that door is probably the culprit. Likely problem areas are the connectors and the splices in the harness. The driver door connector is beside the driver's left foot, so that's easy to check first.

The Comfort Canbus is spliced in the floor harness. The same twisted pair of wires go to all four doors, the CCM, and the cluster, so it's a multi-way splice (more likely several splices). (They also go to the Climatronic module, steering wheel module, and radio "if equipped," but that splice in in the instrument harness.)

The Comfort Canbus is the orange/green and orange/brown twisted pair. Maintain the twist if you make a repair. Also note that all the Canbuses use an orange/brown wire (for Can Low); the orange/green (Can High) distinguishes the Comfort Canbus.

I just noticed you have VCDS... can VCDS see the driver window motor? If the Canbus is the issue, it won't be able to.

On the other hand, if you can control other windows from the driver door, and VCDS can see the driver window module, then there's something local wrong in the door, i.e. wiring between door lock module and window motor. But not much there.

One other possibility: there's a diode in the puddle light (part of the socket/fixture), but if it failed as a short, I'd think the door would always be "open." But it's easy enough to unplug and eliminate, no tools required.
 

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Discussion Starter · #5 ·
The puddle light gets its signal directly from the microswitch in the door lock module, while the interior lights (and the door open indication on the dash) get the signal via Canbus. Specifically, the door lock module is wired to the window controller, which has the Canbus node built-in. It puts the switch status on the Comfort Canbus network where it is read by the CCM (to turn the interior lights on) and the instrument cluster (to indicate "door open" and to pass it on to the ECM so it can prime the fuel).

Can you control the other windows and locks from the driver door? If not, the Canbus to that door is probably the culprit. Likely problem areas are the connectors and the splices in the harness. The driver door connector is beside the driver's left foot, so that's easy to check first.

The Comfort Canbus is spliced in the floor harness. The same twisted pair of wires go to all four doors, the CCM, and the cluster, so it's a multi-way splice (more likely several splices). (They also go to the Climatronic module, steering wheel module, and radio "if equipped," but that splice in in the instrument harness.)

The Comfort Canbus is the orange/green and orange/brown twisted pair. Maintain the twist if you make a repair. Also note that all the Canbuses use an orange/brown wire (for Can Low); the orange/green (Can High) distinguishes the Comfort Canbus.

I just noticed you have VCDS... can VCDS see the driver window motor? If the Canbus is the issue, it won't be able to.

On the other hand, if you can control other windows from the driver door, and VCDS can see the driver window module, then there's something local wrong in the door, i.e. wiring between door lock module and window motor. But not much there.

One other possibility: there's a diode in the puddle light (part of the socket/fixture), but if it failed as a short, I'd think the door would always be "open." But it's easy enough to unplug and eliminate, no tools required.
Wow, thanks for that info! Yesterday I had to go shopping and now the puddle light is not working either. My car has an ancient version of the CAN gateway (pre-2000) which can not be reached over VCDS and I can control all the windows by the driver door buttons. I remember that the puddle light was working but flickering a lot..

Time to cool down my head and dismount the whole door again. I have another micro switch laying around so replacing it wouldn't be that hard. What really confuses me is that some time ago I teared apart one of these switches and noticed that there's not much that can go wrong in there, it's a pure mechanical switch. Maybe the board solders got cracked again (!!!!) or maybe one of the wires that connect the micro switch to the lock board is damaged. I'll only find out when i get there.

Thanks for the info, tough!!
 

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