DSC restricted/start assist failure

Chri5J4 · 09-29-2017, 06:06 PM

Hi,

I've been experiencing an intermittent problem with my 335i e92 coupe. warning light on dash appears, centre console 'faults' reports start assist deactivated and DSC restricted (brake pressure sensor failure).

Had the car read by local garage, no fault code present, they test drove the car for a week fault didn't occur. They have advised me to wait for the problem to become permanent before fixing it.

I've purchased a BT cable and I plug it in regularly but no codes present relating to the hydro or pressure sensor. When the fault is present, I leave the car running, plug it in and no fault code thrown. I switch the car off, everything goes back to normal. Fault re-appears randomly, sometimes when the car is stationary, sometimes during driving at varying speeds.

Its a 2008 model with 97000 on the clock. I believe the pressure sensor is internal.

I've read about the brake pressure issues with the Ate Teves MK60 units, which I believe is the Hydro unit in my car.

I'm confused as to why there is no fault code stored and subsequently, don't want to run the risk of removing the unit, getting it repaired, only to discover the problem is still present and related to another aspect of the DSC/ABS system, i.e. a wheel speed sensor (one of which I have replaced).

The car has various problems, one of which is a sticking parking brake (left rear), which is this weekends job. I wonder if this could be the cause?

Just curious as whether anyone else has experienced this as an intermittent fault instead of a complete failure. I'm probably kidding myself a little when in reality it just needs a new Hydro unit!

Any help/ thoughts greatly appreciated.

Chri5J4 · 01-05-2018, 09:58 AM

So, this seemed like the dreaded DSC unit failure, however, I thought I would provide an update.

I 'think' I have tracked down the problem to a sticking brake caliper and pads on the rear left wheel.

Since dissembling, cleaning, re-greasing and reassembly, the dashboard warning has not reoccurred. This was several months ago and the problem tended to re-occur every week.

Fingers crossed.

09-29-2017, 06:06 PM	#1
Chri5J4 New Member 0 Rep 12 Posts Drives: BMW 335i Join Date: Sep 2017 Location: Manchester, UK iTrader: (0)	DSC restricted/start assist failure - no fault code Hi, I've been experiencing an intermittent problem with my 335i e92 coupe. warning light on dash appears, centre console 'faults' reports start assist deactivated and DSC restricted (brake pressure sensor failure). Had the car read by local garage, no fault code present, they test drove the car for a week fault didn't occur. They have advised me to wait for the problem to become permanent before fixing it. I've purchased a BT cable and I plug it in regularly but no codes present relating to the hydro or pressure sensor. When the fault is present, I leave the car running, plug it in and no fault code thrown. I switch the car off, everything goes back to normal. Fault re-appears randomly, sometimes when the car is stationary, sometimes during driving at varying speeds. Its a 2008 model with 97000 on the clock. I believe the pressure sensor is internal. I've read about the brake pressure issues with the Ate Teves MK60 units, which I believe is the Hydro unit in my car. I'm confused as to why there is no fault code stored and subsequently, don't want to run the risk of removing the unit, getting it repaired, only to discover the problem is still present and related to another aspect of the DSC/ABS system, i.e. a wheel speed sensor (one of which I have replaced). The car has various problems, one of which is a sticking parking brake (left rear), which is this weekends job. I wonder if this could be the cause? Just curious as whether anyone else has experienced this as an intermittent fault instead of a complete failure. I'm probably kidding myself a little when in reality it just needs a new Hydro unit! Any help/ thoughts greatly appreciated.
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01-05-2018, 09:58 AM	#2
Chri5J4 New Member 0 Rep 12 Posts Drives: BMW 335i Join Date: Sep 2017 Location: Manchester, UK iTrader: (0)	So, this seemed like the dreaded DSC unit failure, however, I thought I would provide an update. I 'think' I have tracked down the problem to a sticking brake caliper and pads on the rear left wheel. Since dissembling, cleaning, re-greasing and reassembly, the dashboard warning has not reoccurred. This was several months ago and the problem tended to re-occur every week. Fingers crossed.
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