[sam335i07]

I have searched with no luck. I've got an 07 335i Sedan. The driver mirror is completely dead. Passenger folds fine and adjusts the glass fine. I swapped the driver glass adjuster to the passenger side and it works fine there. I don't know what voltage or ohms I should get at the connector that plugs into the mirror after pulling off the door panel. I do have 12 volts on one wire but nothing anywhere else. Took off the colored trim from mirror assembly and no wires seem to be cut or missing. Im starting to think the whole mirror is shot but it makes no sense that nothing works. Any ideas or a diagram of wiring I can reference? I appreciate any help I can get

Thanks

[djh2]

Try looking around this site https://www.newtis.info/tisv2/a/en/e...erior-mirrors/

[polestar]

Hi,

As djh2 said in post #2, you can start with newTIS to get the wiring diagrams and an idea of the whole system. From 2007, there is a change in the wiring diagrams, so choose the right one for your BMW.

This is going to be a long post (sorry) with a list of areas you can look in to, but hopefully one of them will help you find out what is wrong. The first ones are simpler that you could check without tearing anything apart, so start from there. The later steps are fun but takes patience and time. I did the same as part of the folding mirror retrofit when I couldn't get it work the first time as both mirrors looked dead. Still working on it, but at least both the mirrors fold now. I did a fairly good amount of troubleshooting. Please proceed with care and at your own risk :=)

1. Check Fuses (Fuse 66 or 21).

2. If you have ISTA-D or Carly, run diagnostics. FRM talks to driver side switch cluster and mirrors using LIN bus signals, so if its broken it will show up as a fault code. It did in mine, when I disconnected the driver side switch.

3. If you have 3 pin connector at the mirror assembly plug, you should get 12V with ignition ON between pins 4 (ground) and 6 (battery).

4. Between pins 4 and 5 (LIN bus) it's around 9 V with a multimeter. With this you know LIN bus is probably available. If you have access to an oscilloscope, you can see the actual LIN bus signal. When you operate the driver side switch controls to the driver mirror (slider switch position selected for driver mirror), the width of pulses of the LIN bus signal should change. This way you know the signal is available to the mirror. I have attached a picture.

5. Now you can move a bit higher up (electrically speaking). Disconnect the LIN bus controller that sits on three clips on the mirror assembly. Picture attached. Connect the ground test lead of multimeter to somewhere in the car (typically the door hinge). Then test each connector pin of the LIN bus controller (8 pins in total I think) with the positive (red) test lead. By operating the mirror glass direction switch. Not all pins may show a signal. For me, the one's that show signal switched between 12V and around 3V when the driver switch was operated. I'm still looking for more info on what each pin is for. So I know exactly what each pin should react on inputs from driver.

6. Cut the two wires that go to the folding motor assembly. Connect the multimeter leads to the wires that comes from the LIN bus controller as mentioned above. When the mirror folding button is pressed, the voltage should be +/- 12V depending on which direction the FRM is commanding the motor to rotate.

7. Remove the mirror assembly and clean the connectors with contact cleaner. I have read in many forums that this has fixed mirror problems you mentioned. There are two connectors. One connector that connects mirror assembly to the door and another connector that connects the mirror glass movement mechanism to the mirror assembly. The second one is more likely to be a culprit.

8. I don't know if this is recommended, but fixed the folding problem for my mirrors. Sometimes, the gears in the folding motor assembly gets stuck. When the motor draws too much current, perhaps there is some shut down logic in the ECU. Anyway, you can try spraying liberal amounts of WD 40 and let it stay for a couple of hours at least, to loosen the gears. I have attached a picture to show a hole that you can spray WD-40. I myself am a bit careful using WD-40 , so please do it to the mirrors if you have no other options. After WD-40 spray lithium grease or similar for lubrication.

9. Remove plug 14260 from FRM. (Location: https://www.newtis.info/tisv2/a/en/e...i-lim/AioqZS49 and Connector layout: https://www.newtis.info/tisv2/a/en/e...i-lim/CTU7wiOn ). Do a continuity test with multimeter. Pin 23 of FRM plug 14260 --> Pin 5 or driver side mirror plug (LIN bus). Pin 22 of plug 14260 --> passenger side mirror plug pin 5.

10. You can cut the wires to the folding mirror motor and connect it to an external 12V supply to check if the motor assembly works. Avoid keeping the supply for too long if the mirrors don't move as it might burn the coils in the motor.

Keep us posted if any of these helped you locate the problem.

Best of luck!

[gbalthrop]

Originally Posted by sam335i07

...07 335i Sedan. The driver mirror is completely dead...Any ideas or a diagram of wiring I can reference?

Check your build date on the door sticker. I am assuming your vehicle was built after 3/1/2007 and before 9/1/2007, so I link circuit diagrams for that build interval. If built BEFORE 3/1/2007, drill down and select earlier version.

There are two variants for the wiring for the exterior mirror for your 2007 335i E90: Linbus & NOT Linbus. The wire colors are the same for each variant, but on the Linbus the wire SIZE is slightly smaller for the Blue/Brown and Blue/Gray wires (.35mm2) as compared to the Blue/White wire (.50mm2). All three wires are the same size on the NOT Linbus variant (.50mm2).

Linbus:
https://www.newtis.info/tisv2/a/en/e...irrors/vH1jDWk

NOT Linbus:
https://www.newtis.info/tisv2/a/en/e...irrors/vQYjPw8

ANYONE know another way to tell whether your system is Linbus or not -- Option code in VIN decoder, etc.?

George

[nsjames]

they also break the wires at the pivot point.

so check for broken wires.