Interior lights only works on one side of the car

espenhb · May 21, 2020

Got an issue with the interior lights in the van. The three lights over the kitchen works just fine, but on the passenger side both lights in the roof just inside the door are dead. Hoped it would just the bulbs that needed to be swapped, but I pulled out the lamps today to measure with a meter, and they both gave out 0.07 volts...

There has been some sort of a water leak in the general area of the light closest to the passenger seat, but if that was to cause anything it would blow the fuse, wouldn't it? And from what I understand reading the manual all interior lights share the same fuse, so that can't be the case. Or have I misunderstood something?

Also; kind of struggling to figure out what is what in the fuse box under the drivers seat. Anyone have a diagram?

It's a 2004 T5.

flying banana · May 21, 2020

swap the bulbs with ones you know that work from the other side to confirm the bulbs first. water may have blown them

WelshGas · May 21, 2020

espenhb said:
Got an issue with the interior lights in the van. The three lights over the kitchen works just fine, but on the passenger side both lights in the roof just inside the door are dead. Hoped it would just the bulbs that needed to be swapped, but I pulled out the lamps today to measure with a meter, and they both gave out 0.07 volts...

There has been some sort of a water leak in the general area of the light closest to the passenger seat, but if that was to cause anything it would blow the fuse, wouldn't it? And from what I understand reading the manual all interior lights share the same fuse, so that can't be the case. Or have I misunderstood something?

Also; kind of struggling to figure out what is what in the fuse box under the drivers seat. Anyone have a diagram?

It's a 2004 T5.

After checking the bulbs, as above, I would look for and check the earthing point and or take off for the circuit to the affected side for corrosion. This may be situated behind the trim where the water leak was.

Loz · May 21, 2020

They are normally a switched earth so should have 12v at the lamp.

WelshGas · May 21, 2020

espenhb said:
Got an issue with the interior lights in the van. The three lights over the kitchen works just fine, but on the passenger side both lights in the roof just inside the door are dead. Hoped it would just the bulbs that needed to be swapped, but I pulled out the lamps today to measure with a meter, and they both gave out 0.07 volts...

There has been some sort of a water leak in the general area of the light closest to the passenger seat, but if that was to cause anything it would blow the fuse, wouldn't it? And from what I understand reading the manual all interior lights share the same fuse, so that can't be the case. Or have I misunderstood something?

Also; kind of struggling to figure out what is what in the fuse box under the drivers seat. Anyone have a diagram?

It's a 2004 T5.

This might help.

See page 52. The lights above sliding door are on a spur circuit.

TripleBee · May 21, 2020

What van do you have? T5, T5.1, T6, T6.1? As from the T5.1 there aren't any bulbs in those lights. They are LED's.

WelshGas · May 21, 2020

TripleBee said:
What van do you have? T5, T5.1, T6, T6.1? As from the T5.1 there aren't any bulbs in those lights. They are LED's.

2004 T5 according to the original post. :thumb

flying banana · May 21, 2020

wow. you try and help and this is what you get ? I suspect theres nothing wrong with the sodding lights

TripleBee · May 21, 2020

The lights share the same 12V feed, but do have different earth connections.
My guess would then be, or a bad earth connection, or a damage in the 12V feed on the offside.

espenhb · May 24, 2020

Thanks for all the responses! Got a ton of stuff on my plate, so sorry for the late reply, flying banana.

Seems like I'm in for a dive into the floor under the kitchen unit, Welsh Gas. Thanks for the link!

WelshGas · May 24, 2020

espenhb said:
Thanks for all the responses! Got a ton of stuff on my plate, so sorry for the late reply, flying banana.

Seems like I'm in for a dive into the floor under the kitchen unit, Welsh Gas. Thanks for the link!

I don’t think you’ll find anything under the kitchen floor, more likely the trim above the B pillar on that side.

joessenavn@outlook · Aug 11, 2021

Hi, some sort of the same issue with my cali... I have checked all fuses, measured 12 v at each side of the fuse. At the lamp I measure 0,1-0,3 volt, but if I try to measure + towards the earth in the 12 v outlet beside the sink, I measure -12 v...! Actually to the brown cable as well! This does not make sense to me at all. Any ideas?

joessenavn@outlook · Aug 12, 2021

Where does the earthing go? It could happen that there has been some water intrusion somewhere, or that there are cables that are broken? Any wiring diagram and cable routing diagram that can be used for fault finding? This is a California 2006 model.

flying banana · Aug 12, 2021

You will measure -12v if you just swap the leads round on the meter. Are you sure they are the correct way around?

joessenavn@outlook · Aug 13, 2021

There were some strange measures when trying do measure against the 12 v plug. Now I have done measures straight to the battery, that is easier. And see that I measures + 12v from between + side of battery and the red/green cable at the light. This seems to be some kind of a shortage, but I am not able to see exactly 0 v when measuring to -. The + seems to be "floating", potentially because of water? Or something else? Any idea where to start looking? Does the cable routing go up along the "bar" on the side where the battery sits underneath the seat? I have noticed a time or two that there was a small water leakage in thru the area where the lights sits in the front cabin, and that resulted in a broken fuse. This has been working since fuse was replaced.

joessenavn@outlook · Aug 13, 2021

And, by the way the right hand side in the cabin measures seemed to be more in line with expectations... But there the earthing is not correct (seems like there is +12v but earth is more floating). Why is there a difference between kitchen side and the other?

joessenavn@outlook · Aug 16, 2021

I begin to believe the earth is floating or not present. Seen that also on the ABS sensor rear, potential soldering issue that dissolves if water/humidity appears. So my understanding is that there are a few points were the earth is split (from 1 to 2 to 3), and first place to look for is at top cover where the seat belt goes in. Behind here there should be some splices... Anybody that has experience on this??

joessenavn@outlook · Aug 23, 2021

It turns out that there is no continuity between the fuse (udner the seat) and the + at the light in the ceiling left side. So I have taken off the covers at the door (left hand driven, so it is the left front door. I have continuity from the red/green cable at the lower end behind the cover and up to the light, but not the other way back to the fuse. I have taken out the seat and have started checking underneath there. Not possible to see any tear or that lines are broken... However, Is there a split in the cabling somewhere underneath there on the + cabling?? Actually it seems like there is the same problem also on the right hand side (lights), this line is red/yellow. I believe these goes to two different fuses, or are they connected somewhere also? Would be thankful if anybody could help

joessenavn@outlook · Aug 24, 2021

So, there was the problem solved. Measured back towards the light in the ceiling, found connection approximately at door lock. BUT, just below, at the floor there was no connection. It did not look like there could be any connections inside the isolation/tape, but there were too many leads coming down from above compared to how many green/red lines that continued. So, unwrapped the cable lot, and found the broken link. See pictures, for help to others in case same thing happens.