BMW M5 Forum and M6 Forums banner

Can Anyone Help? Confusing Electronics Issue...

1K views 8 replies 5 participants last post by  apetrov1x5 
#1 ·
Good Evening fellow members,

Today I collected my beloved M5 from the classic car restorers where it has been since March having a host of bodywork seen to. The works went a lot further than we anticipated and in the end the whole car has been repainted less the roof! It now looks truly fantastic with the guys at AR Griffiths in Darley Abbey Mills, Derby having endowed the car with a glass like finish to it's bodywork.

I suspect the cause of these electronic issues it seems to have developed are due to the battery being disconnected for some time during the work due to it discharging. They are bringing in their electronics specialist in tomorrow afternoon for me to try and sort these issues out but in the mean time could anyone offer any insight... The following things are playing up;

- Passenger side door mirror not folding or moving.
- Radio on light illuminates on the nav screen but no sound or ability to show radio / changer screen. Nav does load up but the mapping doesn't show any roads, very odd. Also the retrofitted parrot bluetooth connects but no audio is played.
- The outside temperature gauge show -40C and does not change.
- A/C compressor cannot be heard clicking in when switching the system on.
- PDC long tone warning buzzer goes off when reverse is engaged and the system does not work at the front or back.
- Auto self level function (the roll up and down when first turning on) on the xenons on dipped beam does not happen (can't remember if they self level every time but they look lower on the road than I remember too).
- Date reset itself again after the car had been standing for a while this afternoon.

All other electronic functions on the car seem to be working fine.

A confusing combination of faults to my mind. The car has had bumpers and mirrors off during the work but the chap at the workshop said PDC etc only seemed to be push together connectors which he re-assembled it.

I will hopefully have some more clarity on what is at fault and the problems resolved tomorrow, but in the mean time I would greatly appreciate the knowledge / experience / insight only the M5 Board can give!
 
See less See more
#2 ·
I would start first by putting a fresh battery in your car and making sure all the connections are snug. Then:

- Passenger side door mirror not folding or moving.
These fail a lot. If they had it off I would hold them responsible. Try pushing it with your hand while you fold them up.

- Radio on light illuminates on the nav screen but no sound or ability to show radio / changer screen. Nav does load up but the mapping doesn't show any roads, very odd. Also the retrofitted parrot bluetooth connects but no audio is played.
Ask them if they jump started your car.

- The outside temperature gauge show -40C and does not change.
They either didn't hook your ambient air temp sensor back up or they broke it.

- A/C compressor cannot be heard clicking in when switching the system on.
This should fix itself when you fix your ambient air temp sensor.

- PDC long tone warning buzzer goes off when reverse is engaged and the system does not work at the front or back.
They forgot to hook your PDC back up or broke the sensors.

- Auto self level function (the roll up and down when first turning on) on the xenons on dipped beam does not happen (can't remember if they self level every time but they look lower on the road than I remember too).
This works or it doesn't work?

- Date reset itself again after the car had been standing for a while this afternoon.
I would get a new battery and check the connections.
 
#4 ·
I would start first by putting a fresh battery in your car and making sure all the connections are snug. Then:


These fail a lot. If they had it off I would hold them responsible. Try pushing it with your hand while you fold them up.


Ask them if they jump started your car.


They either didn't hook your ambient air temp sensor back up or they broke it.


This should fix itself when you fix your ambient air temp sensor.


They forgot to hook your PDC back up or broke the sensors.


This works or it doesn't work?


I would get a new battery and check the connections.

Mirror - Ok I'll try pushing it myself and see what luck I have maybe it will come back to life...

Radio / Nav not working - Do you mean as in pushing it along or with a power pack? I know they had to start it using a power pack as the battery had become discharged, but I don't know if they jump started it by pushing it along? Would jump starting it have had an impact if they did?

Air temp & AC & PDC - Hopefully this will be a simple fix and we will be back in after a code read and fault find....

Lights - I cannot remember if they scroll up and down when you first turn them on? I think it used to do that and my 135 does this when it's xenons power on. The M5 now doesn't do this, they come on at a low angle and stay low.

Date and time keeping - Hopefully it will have remembered when I start it to take it down this afternoon!

I really appreciate your help Frye, very helpful!
 
#3 ·
I would make sure the battery is charged up. Ambient temp sensor may go back to normal after a few on/off cycles.

Does radio shut off after roughly 2 minutes? If so, the NAV unit may have gotten fried. Disconnecting the battery before it completely spins down will do it. Don't ask me how I know. :)

For the headlights, make sure they reconnected all of the plugs to the headlights if those were removed. I made that mistake myself when swapping the lenses.
 
#5 ·
I gave the car a run for a good hour yesterday so hopefully that will have restored it to a good level of charge.

The radio on light is illuminated but no sound can be heard from start up and this doesn't change once it has been on a while. You also can't seem to turn the radio off either - the light remains on no matter what you try! Hopefully by virtue of the fact the nav unit does start up and you can input an address of the main screen (this and the Set menu are about the only functions that remain accessible) means that it isn't shot!

I'll get them to look into the headlight cables and double check that.

Thank you very much for your help!
 
#7 ·
ok check the fuse on the radio in the trunk most likely the tail lights were out and got something wet other thought is when they pulled the rear bumper getting to the bolts from inside the trunk they disconnected something. as far as the pdc sensors check to make sure the main harness connection is plugged in does the pdc light flash?

ac fix the ambient temp sensor, if ac does not work then do an ac recharge or real basic start car up and look at the compressor does the clutch spin with ac on

mirrors are the mirrors plugged in

headlights you have broken adjusters thats why they are not doing there sweep
 
  • Like
Reactions: DesertTech
#8 ·
Hi guys,

Thank you all for your replies... Having had the car looked over briefly by the car electronics guy - some of the issues were resolved and others remain hopefully to be fixed tomorrow morning when the car goes back to the garage for the day.

- The Auto levelling of the lights was a simple fix with a slightly bent terminal in a plug connector I believe - they now swing happily to a nice level beam.
- The faults with the PDC were traced to 2 sensors in the front bumper - this is coming off tomorrow for further investigation; fingers crossed they can be fixed.
- I have been given re-assurance that the ambient temp sensor is not reading at all - hence -40C showing! This should be fixed with the bumper off tomorrow and in turn should cure the A/C not operating.
- Passenger door mirror; the switch is speaking to the main computer but then nothing happens when a signal is sent from there to the mirror. The door card is coming off tomorrow for investigation...
- The radio not working has been tracked down to water damage on the top of the unit in the boot. This was to my astonishment as I tried to imagine how water could have ingressed into the boot. And the you mentioned the rear lights being out... and I pulled up a picture of the car on my phone mid project outside the workshop with no lights in and it dawned on me this must have been how this happened! One for discussion tomorrow....!!!

Hopefully come tomorrow afternoon most of these issues will have been addressed. I am very grateful for the knowledge people have taken time to share on this thread. It has been very helpful! :cheers: :M5launch:
 
#9 ·
Hi guys,


- Passenger door mirror; the switch is speaking to the main computer but then nothing happens when a signal is sent from there to the mirror. The door card is coming off tomorrow for investigation...


Hopefully come tomorrow afternoon most of these issues will have been addressed. I am very grateful for the knowledge people have taken time to share on this thread. It has been very helpful! :cheers: :M5launch:
Hi, did you manage to get the passenger mirror working?
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top