[Timppa]

Hello Everyone,

First time posting something here on the forum

For a while now I have this problem that my rear light right does not work, It also appears as a fault on my dashboard.
I have inspected the sensor (piece where the 3 lightbulbs are in), and only the regular driving light does not work (the middle one). I saw there was some 'burn'-damage there so I replaces the faulty sensor with a new one. This did not solve the problem.
A local dealer (not BMW) has checked the fuse box and the wiring in the trunk (where the wiring bends, when opening the trunk), and can not find any problems there.
Could this be a canbus problem? Or anything else I could try first?
And is there a way I could deal with this myself? or should I go to a BMW-dealer?

Thank you in advance!

[tlow98]

I think the early model light units had issues and needed to be replaced. Do a search there are some common issues out there regards to these lights.

[gbalthrop]

Originally Posted by Timppa

...my rear light right does not work, It also appears as a fault on my dashboard. I have inspected the sensor (piece where the 3 lightbulbs are in), and only the regular driving light does not work (the middle one). I saw there was some 'burn'-damage there so I replaces the faulty sensor with a new one. This did not solve the problem...

Welcome to the Forum!

Is the tail light bulb that is NOT lighting on the Fender (Outer) or on the Tailgate (Inner)? If you were concerned with wiring at the tailgate hinge plane, I presume it is the "Inner" tail light (E81) on the Tailgate.

TIS has good circuit diagrams, and also "Installation Location" and "Connector Views" for components and Connectors. Here are FRM circuit diagram, Side Light/ Parking Light Diagram (E81 is Inner & E47a is Outer tail light), and Installation Location and Connector View for E81/ Inner, along with Procedure for bulb replacement:
https://www.newtis.info/tisv2/a/en/e...module/r6wjBLF
https://www.newtis.info/tisv2/a/en/e...-light/i7o2pTr
https://www.newtis.info/tisv2/a/en/e91-320d-tou/S6Wh2wJ
https://www.newtis.info/tisv2/a/en/e...d-tou/CTLOLnQW
https://www.newtis.info/tisv2/a/en/e...lights/E9qcaeW

I would test for 12V+ at Pin#3 of Connector X328 (at E81) the Yellow Violet wire, and also for 12V+ at the bulb socket. Also check for continuity to ground at Pin #2, Brown wire & bulb socket. Ground failure is as likely as failure of 12V+ wire/connection.

Please let us know what you find,
George

[Timppa]

Originally Posted by gbalthrop

Welcome to the Forum!

Is the tail light bulb that is NOT lighting on the Fender (Outer) or on the Tailgate (Inner)? If you were concerned with wiring at the tailgate hinge plane, I presume it is the "Inner" tail light (E81) on the Tailgate.

TIS has good circuit diagrams, and also "Installation Location" and "Connector Views" for components and Connectors. Here are FRM circuit diagram, Side Light/ Parking Light Diagram (E81 is Inner & E47a is Outer tail light), and Installation Location and Connector View for E81/ Inner, along with Procedure for bulb replacement:
https://www.newtis.info/tisv2/a/en/e...module/r6wjBLF
https://www.newtis.info/tisv2/a/en/e...-light/i7o2pTr
https://www.newtis.info/tisv2/a/en/e91-320d-tou/S6Wh2wJ
https://www.newtis.info/tisv2/a/en/e...d-tou/CTLOLnQW
https://www.newtis.info/tisv2/a/en/e...lights/E9qcaeW

I would test for 12V+ at Pin#3 of Connector X328 (at E81) the Yellow Violet wire, and also for 12V+ at the bulb socket. Also check for continuity to ground at Pin #2, Brown wire & bulb socket. Ground failure is as likely as failure of 12V+ wire/connection.

Please let us know what you find,
George

Hello, thank you for your great reply.
It is indeed the E81 with X328 connector.
And with this link you provided:
https://www.newtis.info/tisv2/a/en/e...lights/E9qcaeW
It is the 2nd picture, 2nd bulb:
Rear light in rear lid: 2. Bulb, rear light

I was thinking to take pictures, but now it is not needed anymore
I don't have any meter to check the power on this, I am not great with electric stuff...
I do remember my local dealer checking some of these (not sure if he checked all), and they all had power
I also know he checked the groundings themself, because he made a mess in my trunk!, so he removed the panels.
But I do see that it is all connected to the footwell module.
I was reading that they could remove a bad code from there(if that is the issue) to resolve this problem, that the footwell module automatically cuts off the electricity because of safety issues.
But I also read that sometimes they just force you into replacing the whole module and I really don't feel like spending my money for that for 1 silly light that doesn't work.

[gbalthrop]

Originally Posted by Timppa

...I don't have any meter to check the power on this, I am not great with electric stuff...[neither are most people working in shops -- in 2 hours or less, you can know more than they do & diagnose the problem YOURSELF ]
I do remember my local dealer checking some of these (not sure if he checked all), and they all had power [it takes BOTH 12V+ AND GROUND -- that's why they call it a circuit ]

All your other bulbs in that holder, AND the similar bulbs on the other side work fine, so you FRM Module is OK. You have a simple wiring issue -- simple as far as cost of repair if you Do It Yourself. NOT simple if you have to rely on others. If you just get a cheap multimeter like one linked in Amazon UK page below, you can learn how to measure Voltage and Ohms (Resistance or Continuity) and test things yourself:
https://www.amazon.co.uk/s?k=multime...f=nb_sb_noss_1

Make sure the meter has a manual which explains how to test Volts & Ohms, DC (Direct Current). If any questions or problems, post back & I'll explain use, and how to test.

It's as simple as plugging the probes into the correct sockets, selecting the correct measurement Type & Range (e.g. Volts, 20V DC or less), turning on the meter, contacting the 12V+ wire with Red Probe, known good chassis ground with Black Probe, and reading Voltage. You can test at the Jumpstart Terminals under the hood to see how meter works. Don't worry about damaging something or getting shocked. NO current is flowing through your meter, you are simple measuring "Electric Potential" between (1) "B+" or Positive Battery Terminal (12V+) and (2) Chassis Ground which is connected to Negative Battery Terminal.

Measuring Ohms or Resistance is even easier, when you are testing "Continuity" or connection to Ground. Select Ohms/Resistance. Touch Probes together, and Ohms/Resistance should be 0 Ohms or nearly so (.01) meaning virtually NO resistance. With the Probes NOT contacting each other, resistance is "Infinite" = 1 on most meters (open circuit). So if you contact the Brown Ground wire with one probe and a known good chassis Ground with the other probe, Ohms should go from "1" to "0" (or nearly zero). If it does NOT, you have an "open circuit" or detached/ broken ground wire.

Please let us know what you find,
George

[lowrydr310]

I had a similar issue on my car. The problem is that there was a small amount of corrosion at the base of one bulb where it contacts the metal plate in the housing. I scuffed them with steel wool and added a small amount of dielectric grease and all has been good for the past year.

[Timppa]

Hi!

I will try to get my hands on a multimeter and report back , Thanks!

Originally Posted by gbalthrop

All your other bulbs in that holder, AND the similar bulbs on the other side work fine, so you FRM Module is OK. You have a simple wiring issue -- simple as far as cost of repair if you Do It Yourself. NOT simple if you have to rely on others. If you just get a cheap multimeter like one linked in Amazon UK page below, you can learn how to measure Voltage and Ohms (Resistance or Continuity) and test things yourself:
https://www.amazon.co.uk/s?k=multime...f=nb_sb_noss_1

Make sure the meter has a manual which explains how to test Volts & Ohms, DC (Direct Current). If any questions or problems, post back & I'll explain use, and how to test.

It's as simple as plugging the probes into the correct sockets, selecting the correct measurement Type & Range (e.g. Volts, 20V DC or less), turning on the meter, contacting the 12V+ wire with Red Probe, known good chassis ground with Black Probe, and reading Voltage. You can test at the Jumpstart Terminals under the hood to see how meter works. Don't worry about damaging something or getting shocked. NO current is flowing through your meter, you are simple measuring "Electric Potential" between (1) "B+" or Positive Battery Terminal (12V+) and (2) Chassis Ground which is connected to Negative Battery Terminal.

Measuring Ohms or Resistance is even easier, when you are testing "Continuity" or connection to Ground. Select Ohms/Resistance. Touch Probes together, and Ohms/Resistance should be 0 Ohms or nearly so (.01) meaning virtually NO resistance. With the Probes NOT contacting each other, resistance is "Infinite" = 1 on most meters (open circuit). So if you contact the Brown Ground wire with one probe and a known good chassis Ground with the other probe, Ohms should go from "1" to "0" (or nearly zero). If it does NOT, you have an "open circuit" or detached/ broken ground wire.

Please let us know what you find,
George

[Timppa]

I had this as well, it worked at first, but then it stopped working all together.
I had few days without a warning, then with a warning, light working, not working,... But now it all doesn't work anymore.
And that part where the corrosion was on, where the lightbulb is in, has been replaced by a new one , but still it doesn't work.

Originally Posted by lowrydr310

I had a similar issue on my car. The problem is that there was a small amount of corrosion at the base of one bulb where it contacts the metal plate in the housing. I scuffed them with steel wool and added a small amount of dielectric grease and all has been good for the past year.

[Timppa]

Originally Posted by gbalthrop

Please let us know what you find

Hi!

I could borrow a multimeter from a friend of mine and this is what I discovered:
Like you said, the 3th connection, yellow-purple wire, is the broken light.
So I checked the volt on that wire and it went to 0.04, so basically nothing.
Then I checked to be sure, the left light and there it jumped to 10.2.
I also checked the grounding like you requested and the ohms went from 1 to 0, so there is no problem there.
Then I tried to check the place where the wires go from the trunk to the car itself (the bending), but after opening it, i noticed that the wires are unreachable or viewable. So basically they charged me in the garage to check the wires, told me they are fine, but they lied! Costing me money for nothing...
So, where do I go from this?
Is there a way to reach the wires myself and fix it or what should I do?

[Timppa]

Not to spam this post, but again a little update:

I removed the plastic panels between the glass and the trunk and I could see the cables going up to where the rubber bending is(between trunk and car).
There seems to be no issues there.
I tried to have a look inside the rubber, but this seems impossible, unless I would cut the rubber open with a knife

[gbalthrop]

Originally Posted by Timppa

...I tried to have a look inside the rubber, but this seems impossible, unless I would cut the rubber open with a knife

I haven't done the job myself, but there are NUMEROUS posts on the forums related to E91 wiring breakage at the hinge plane. Here are two such posts (found by using "Forum Search"), one showing removal of gaiter, sheath or wiring cover from the chassis opening, and another describing the repair by cutting the sheath (Post #8, Last, in thread):
https://www.e90post.com/forums/showp...97&postcount=5
https://www.e90post.com/forums/showt...ailgate+wiring

George

[tonnyguetta]

Well i think the early model light units had issues and should have been supplanted. Do an inquiry there are some regular issues out there respects to these lights.