E46 M3 DSC & Brake Light Illuminated Yellow

[trancenation]

Hello Folks,

After driving our E46 M3 ZCP over a set of paved train tracks (street intersection) the DSC and Brake light illuminated yellow. I ran the car on the BMW Scanner 1.4 and pulled a 5E20 code which said "Pressure Sensor 1". After further research, I was able to narrow this down and my instincts tell me that it could be one of the two Brake Pressure Sensors.

When I unplugged the first Brake pressure sensor (Closest to the firewall of the car) and scanned the car, the same 5E20 code appeared.

When I unplugged the second Brake pressure sensor (Closer to the front of the car), It revealed 5E21 Code, "Pressure Sensor 2" .

This has led me to believe that I have a faulty Brake Pressure Sensor 1. However, after fiddling with the connector and plugging both back in, both lights went away on my drive but then reappeared after going over a mild pothole.


Any thoughts on what this could be? I am considering checking my speed sensors on all fours corners. Or maybe could our tires being oversized have anything to do with this?(245-35-19 front) and (275-30-19 rear)

[echo46]

Not sure, but still could be a faulty brake pressure sensor. Keep us posted.

[trancenation]

Update:

I cleaned the wheel/speed sensors on all four corners and they all appear to be in good shape, so I've ruled those out as my problem. So, I ordered me a master cylinder that comes with two dsc/brake pressure sensors off ebay . I will be doing the replacement of the brake pressure sensor next week and I hope this solves my issue!

[BCS_ZHP]

Read thru this thread, sound like you're experiencing similar

http://www.zhpmafia.com/forums/showthread.php?10464-DSC-Light

[trancenation]

Update: Just replaced the pressure sensor 1 and bled the brakes. So far so good!

[UdubBadger]

This happened to me a bunch on my way to Ohio this summer but so many things were wrong with the car it just went away as everything got fixed. I replaced the sensors, rotors and pads so that was likely it.