Instrument cluster stop working? DSC, ABS, BRAKE lights on? Try this first.

**MATT0404** · 10-10-2009, 09:27 PM

Today my 540i's instrument cluster stopped working while I was driving. The speedometer and RPM's dropped to zero at first. Next came a "check coolant" message on the OBC, then the DSC, ABS, and BRAKE light came on. Next, the temp gauge pegged to HOT, which scared the s**t out of me since I just replaced the coolant system.

I pulled over and ran test #7 on the OBC which read 104C, which is normal, but then it went to -128C. I scrolled over to RPMs and it read 65,545, to which my wife replied "vtec must have kicked in", haha.

So, I was at a loss, I putted the car home and turned it off. I found it weird that even though my headlight switch was in the off position and the key was out of the ignition, my angel eyes remained illuminated. After doing some research I concluded it was probably an ABS sensor, wheel speed sensor, or the ABS module itself. That is, until I stumbled upon this video:

[ame]http://www.youtube.com/watch?v=PmR9ul9Q7aM[/ame]

Same exact problem. I went out and grounded the harness with some wire and everything returned to normal. I explored further and loosened the grounding bolt. As soon as it lost contact my AE's lit up, and as soon as it grounded they turned off.

If you encounter a problem like this, give this a try before spending $300 to rebuild your ABS module, or $550 for a new one. It could save you a lot of money and the headache of trying to troubleshoot everything.

**cal45fan** · 10-10-2009, 10:07 PM

I have seen this before and preached it on this forum.

**MATT0404** · 10-11-2009, 10:02 AM

Really? I couldn't find anything about it when I was searching. I came across a few posts where people said that it could be a ground, but nothing specific. If nothing else, hopefully this thread just makes it more searchable and helps someone else out.

**Blauanzug** · 10-11-2009, 10:17 AM

thanks for the post i'll add it, so that when this happens I won't freak out!

**f355spider** · 10-11-2009, 02:38 PM

Have you tried unbolting the grounds where they connect and wire brush clean everything? That ground point should be working, so I would try to clean it up thoroughly before jumping to a "work around" as a solution. Though rare on a newer car, this is a pretty common issue on 10+ year old cars, and going through all the chassis grounds taking them apart, cleaning and reassembly is a good idea.

**MATT0404** · 10-11-2009, 03:08 PM

Originally Posted by f355spider

Have you tried unbolting the grounds where they connect and wire brush clean everything? That ground point should be working, so I would try to clean it up thoroughly before jumping to a "work around" as a solution. Though rare on a newer car, this is a pretty common issue on 10+ year old cars, and going through all the chassis grounds taking them apart, cleaning and reassembly is a good idea.

Oh yeah, I removed the bolt and found it was clean and free of corrosion. I reinstalled the bolt and tightened it back down and it was fine. I wouldn't leave it with alligator clips as a long-term solution. I should have clarified that in my post.

**f355spider** · 10-11-2009, 05:27 PM

No, I realize you would use a proper set up for a permanent solution, I am just trying to figure out what could be wrong with the factory ground point that is causing the issue. But good to find such a simple solution.

Have any of you seen these aftermarket grounding kits that allow you to add additional grounds from various points on the engine to the chassis? Say from where the coils ground and from fuel pump and other areas. Even almost new cars can sometimes benefit and show improvements on the dyno. I was surprised to say the least.

**RXWLLMSS** · 10-11-2009, 07:46 PM

Ummmmmmm anyone have the locations for the abs module ground wires?! There's so many it's weird.

**MATT0404** · 10-11-2009, 07:54 PM

Originally Posted by RXWLLMSS

Ummmmmmm anyone have the locations for the abs module ground wires?! There's so many it's weird.

The ABS module, from what I understand, grounds to this specific point on the passenger side of the engine compartment. That's what causes the ABS, BRAKE, and DSC lights to come on. Also, I believe this will also throw ABS module malfunction codes when scanned.

**RXWLLMSS** · 10-12-2009, 10:13 PM

It didn't work!

im so sad. it's been 2 years with this problem. i was so stoked when i read this i ran downstairs and tried it. fail. thanks for the info matt.

**MATT0404** · 10-13-2009, 08:50 AM

Originally Posted by RXWLLMSS

It didn't work!

im so sad. it's been 2 years with this problem. i was so stoked when i read this i ran downstairs and tried it. fail. thanks for the info matt.

Sorry it didn't work out for you.

**nine9six** · 11-11-2009, 07:51 PM

This just happened to me with the exact symptoms in the video in the first link and it was that exact ground spot. I took out the bolts and cleaned off the dirt then sanded it down a bit. Put it back together and bam, back in business!

So far I only let the car idle for a few minutes and everything seems a-ok so far. Keeping my fingers crossed.

**jamesdc4** · 11-11-2009, 08:26 PM

Great post! I had the DSC/ABS problem intermittently at the beginning of last spring. The symptoms are a little different, but I'm going to try this anyway to rule it out.

Thanks.

**FP5241** · 11-12-2009, 01:55 AM

Keep us updated James..

Excellent thread Matt.

**MATT0404** · 11-12-2009, 09:09 AM

Originally Posted by nine9six

This just happened to me with the exact symptoms in the video in the first link and it was that exact ground spot. I took out the bolts and cleaned off the dirt then sanded it down a bit. Put it back together and bam, back in business!

So far I only let the car idle for a few minutes and everything seems a-ok so far. Keeping my fingers crossed.

Originally Posted by jamesdc4

Great post! I had the DSC/ABS problem intermittently at the beginning of last spring. The symptoms are a little different, but I'm going to try this anyway to rule it out.

Thanks.

Hope it works for you. Give us an update when you can.

Originally Posted by FP5241

Keep us updated James..

Excellent thread Matt.

**nine9six** · 11-12-2009, 09:59 AM

After driving mine for about 40 miles or so, everything works most of the time. There was this period of 2 to 3 minutes where everything died again but then it came back up. I am hoping it is because I didn't clean the ground area enough. I will take it apart and clean it more later today.

**m5hoot** · 11-16-2009, 09:02 PM

Since your connection seems to be a tad fussy, consider adding a redundant ground to the mix to put the whole issue to bed. The cause could be further down than the bolt. Could be bad connection between body panel and front clip- who knows. I would just add a redundant ground from the bolt to another clean spot. This was a great find guys. Good work.

**bhuang1103** · 11-17-2009, 11:27 AM

Originally Posted by MATT0404

Hope it works for you. Give us an update when you can.

I tried it on mine yesterday. It didn't work. But my symptoms are different.

**98 528i** · 01-04-2010, 09:15 PM

You just saved me a buttload of trouble with that video. I was working on the SAP over the last few days and I had to take my AFE intake out to access the valve and I never tighted the ground tight enough so I had those same symptoms. I was getting ready to check the two front wheel speed sensors since I had the front wheels and the bumper off...phewwww...thanks man.

**MATT0404** · 01-05-2010, 12:42 PM

Originally Posted by 98 528i

You just saved me a buttload of trouble with that video. I was working on the SAP over the last few days and I had to take my AFE intake out to access the valve and I never tighted the ground tight enough so I had those same symptoms. I was getting ready to check the two front wheel speed sensors since I had the front wheels and the bumper off...phewwww...thanks man.

Glad it helped!