BMW 520d F10 - traction control error?

dodzy

Hi folks, query for ye. When taking a quick left turn , on a road with a sweeping bend (where you can accelerate into it) I get an “auto hold / pb failure warning message on screen and warning lights on dash. This will remain on until the next time the ignition is switched off. No issues on restart, unless the exercise is replicated. Never happens under normal conditions; only on rare occasions where I (arguably) take a left turn a little too quickly. No issue when replicating exercise on right side. Any ideas?

*At no point is rear traction even close to lost.

mk7r

dodzy wrote: »

Hi folks, query for ye. When taking a quick left turn , on a road with a sweeping bend (where you can accelerate into it) I get an “auto hold / pb failure warning message on screen and warning lights on dash. This will remain on until the next time the ignition is switched off. No issues on restart, unless the exercise is replicated. Never happens under normal conditions; only on rare occasions where I (arguably) take a left turn a little too quickly. No issue when replicating exercise on right side. Any ideas?

*At no point is rear traction even close to lost.

Could be a wheel bearing or something flexing under the pressure of turning hard

dodzy

mk7r wrote: »

Could be a wheel bearing or something flexing under the pressure of turning hard

How would a faulty bearing throw a warning ?

mk7r

dodzy wrote: »

How would a faulty bearing throw a warning ?

The speed sensor reads the bearing, if it's loose it will flex and they can touch the sensor under hard cornering pressure.

nogoodnamesleft

dodzy wrote: »

Hi folks, query for ye. When taking a quick left turn , on a road with a sweeping bend (where you can accelerate into it) I get an “auto hold / pb failure warning message on screen and warning lights on dash. This will remain on until the next time the ignition is switched off. No issues on restart, unless the exercise is replicated. Never happens under normal conditions; only on rare occasions where I (arguably) take a left turn a little too quickly. No issue when replicating exercise on right side. Any ideas?

*At no point is rear traction even close to lost.

The easiest way to pinpoint would be to get the car on a diagnostic scan to determine what is causing the error as they are logged in the car.

The idrive could just be throwing up a generic warning. ISTA is useful as it will give troubleshooting based on what module is affected.

BavarianCare

Read the codes & freeze frame data.
If you've access to ISTA+ you can use the test plans. However, codes should be enough with this issue