Hi everyone, I would like some advice about my problem, 2 days ago my parking sensors stopped working, same issues as in several other posts, 3 second constant tone and light then flashes on pdc button, I ve checked all the sensors front and rear for clicking and they all work, I have also unplugged front and rear sensors from pdc unit behind fuse box but still get tone and flashing light. Does this mean that the pdc unit is faulted, or could there still be a issue with sensors or wiring and pdc unit has just logged a fault. I have checked through many previous posts but still unsure that if I get clicking from all 8 sensors that they could still be the problem, hoping its the pdc unit as it seems easy to replace.

The 3 second tone just indicates to the driver that there is a fault somewhere n the system and the PDC ECU base shut the system off. If all 8 sensors are clicking then it would indicate that the sensors are fine and the wiring is fine. I would start with ECU and replace it. It doesn't need to be coded, it is just plug and play. You can take a look through ebay for BMW X5 ECU's and off the top of my head a new one from LR will cost around £140.

Cheers

Steve 06MY 4.4 V8 Autobiography Cairns Blue with Navy & Parchment Interior

Thanks for the reply, I was hoping it was the ecu as it seems easier to replace. I will check ebay first, once I remove old one as I believe there is a part number stamped on it. Once again, thank you for your reply.

This may be useful >>

Paul

Thanks Paul, This was one of the links I viewed, it was helpful with identifying the clicking noise you get from the sensors and how to remove the unit from behind the fuse box. Thanks again.

I had the same issue and it ended up being a loose connection on the loom. I had to remove the rear bumper as the connection is sited below the offside rear fuse compartment, behind the bumper section below the fuel filler.

Paul

Rear loom most likely as above. Connectors can get loose or rusty.

strange but they has been working this evening, now wondering whether it is water issue but fault first started when weather was dry and since has been heavy rain and damp, or whether fault has cleared it self. Hopefully it will not come back. .