BMW M5 Forum and M6 Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
1,346 Posts
Discussion Starter #1
Hi guys!

I was just taking a nightly spinn with my M5, and suddenly it said "pling" Oh-well I thought it's range under 50km. So it was, but to my surprise I found the ABS light as well as the brake light the antispinn and my tacho stopt working!!!

All of a sudden.

And what's more, the petrol gage was jumping from empty to about 1/4 of a tank... And you can imagine the pling-pling-pling when my range meter is informing me of low fuel....

So what's up? This sucks....
It was dry outside, +5celsius, I was driving on uneven surfaces in Helsinki center. :mad:
 

·
Registered
Joined
·
1,346 Posts
Discussion Starter #3
BMW changed the sensor, problem still there, they think it's the central unit, price 1000€. Turns out it's probably both.

So I'm looking at an end bill of 1300€, just for a lousy electrical problem...

BMW M5 curse? :crying:
 

·
Registered
Joined
·
4,515 Posts
You may pay to replace "both", but be assured that you did not have multiple failure modes. The shop experts are guessing & throwing parts at your car. You could do the same thing and save labor fees. A good electrical troubleshooter could put a meter/oscilloscope on each 2-wire ABS wheel sensor circuit to verify function (square waves) before replacing them. Frankly, it's easier to soak the customer. Just be aware what's going on at your shop.

I have some wiring diagrams & I need to review them. Thinking further, I seem to recall the four wheel sensors feed the ABS module before proceeding to the lkm light module and ike speedo/odo, so your mechanic may be on the right track.

I surely hope all fuses have been verified good. There are about 4 fuses that can affect the ABS and related speed signals.
 

·
Registered
Joined
·
4,515 Posts
I need to stress the importance of keeping a battery tender (smart trickle charger) on your E39 during periods of storage, longer than 2 weeks. Reduced voltage levels put tremendous strain on electrical modules and components. When your voltage dips under 12 volts, you can prematurely fail or stress expensive modules. The days are over when you store your car for 3 months and find your battery floating at 8 volts or less. Running out and buying a fresh battery may not fix it. Buy a fresh battery every few years, BEFORE it gets weak.

It is similarly important to use care when jump-starting an E39. The wrong polarity may cost you many thousands in electrical repairs.
 

·
Registered
Joined
·
1,346 Posts
Discussion Starter #7
bayerischemotor said:
Well every second start of the car, all systems work fine....

I can´t figure this one out!

:confused:
Well finally got the problem fixed!

It was the Brake control module. But this problem have taken 4 visits to BMW, Changing 1 ABS sensor, and 2 ABS modules, since the first one they changed to was also faulty, and about 7hours of my time, waiting at BMW :sad3:

And the end bill was 1000€ :M5thumbs:

What a total pleasure
:mad:

:cheers:
 
1 - 7 of 7 Posts
Top