I have a 2004 E61 525d SE. During the recent cold spell, I've had intermittent PDC failures. The display says "PDC failure" and the audio/visual parking warnings are disabled. I've identified that the front mid-left sensor doesn't work when this happens (the sensor doesn't "click", the other 7 are clicking away happily).

The problem seems to be temperature dependent and only occurs when the weather freezes overnight. The past couple of days have been above freezing, and there's no problem. Maybe there's a little water stuck somewhere that freezes and causes the problem?

BMW have priced a replacement sensor at ?120, and a local BMW 'specialist' will fit it for ?65, but I'm wondereing whether I can just remove the sensor, dry it out completely (hair dryer?), then replace it.

Has anyone replaced a middle front sensor? Is it easy to remove/replace? I can just about reach it via the front grille, but can't get a good grasp of it.

Any ideas folks?

 

Removing the sensor module itself is pretty easy no screw just snap on clip but to get to it you have to remove the whole bumper since you probably have to use both hands to undo the holder while puling the module out of it.