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Old 08-27-2016, 02:16 PM
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ztom ztom is offline
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Location: Thousand Oaks CA
Join Date: Sep 2007
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Mein Auto: 1997 528i
May have fixed trifecta - front wheel sensors dust

Keywords - trifecta, DSC, wheel sensors, cleaning,steering angle sensor

1. Trifecta lights (do search if you have not heard of this)
2. Trifecta would light up only after a long drive, as if heat related
3. Restarting the engine clears the trifecta, only to return, more often if car is hot
4. Events were seldom (months) and eventually became daily event

What I believe is the root cause in this case
1. I do NOT think it is the DSC module. Had the codes read and it point to both FR and FL wheel sensors, & did not show a module failure code
2. Inspected the front sensors, had a lot of metal filings on the magnetic tip of the sensor, so I cleaned it off

How I cleaned off the sensors:
1. Wet a paper towel with hand sanitizer, couple pumps
2. Gently wiped the sanitizer onto the sensor to coat up the metal filings, then wipe off the sanitizer. The idea here is the sanitizer is viscous and holds the metal filings so they don't jump back onto the sensor. Then the residual sanitizer is mostly alcohol and water so leaves no residue.
3. Rolled the paper towel into a tip and put it into the hole where the wheel sensor was. Rotated the rotor to do some wiping. But looked pretty clean. careful not to leave bits of paper towel in the hole.

Tips on removing sensor:
1. It would have been hard to pull by hand. Many miles caused the sensor to be stuck in by dust So I put some small handle pliers on the end and very slightly rocked the sensor as I pulled, to un-seize it from the dust.
2. Putting the sensor back in, I rotated it back and forth to kind of scrub the walls of the hole to loosen up and clear other dust in there. Checked, that dust was nonmetallic

Main take-away:
1. Get the codes read but don't conclude too soon the DSC is bad.
2. It was not related to the steering angle sensor because it didn't throw that code, also that sensor would not be heat related.
3. It is possible for the DSC to have faulty connections and throw an incorrect code. Even then it may not be the DSC; I would have removed and reinserted the DSC connector to make sure good contact.
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Old 08-27-2016, 04:58 PM
FredoinSF FredoinSF is offline
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Location: Reno NV & Healdsburg CA
Join Date: Nov 2009
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Mein Auto: 4 BMWs, 1 Mini, 1 Vespa
This is fairly common in the Gen 1 new MINI's (R50 and R53) and your fix is correct. The sensor is the cause of the trifecta of warning lights. On the MINI side, I believe they recommend replacing the sensor, but if cleaning it works, even better.
This is manking me miss my MINI, wish I had a couple of extra garage spaces cuz it was hard to let go of that car.

Last edited by FredoinSF; 08-27-2016 at 04:59 PM.
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