Citroen C4 Picasso 2015 front parking sensors not working

[TecJunkie]

Please can you help.
Someone reversed in to my can and now the parking sensors not working.
I have an error code U131D no coms with parking assistance ECU. Permanent fault.
I have checked the visible wiring but cant see any damage.
I have checked the resistance on pin1 and 2 of the sensor ok.

How can I find out what is causing it to now work.
Regards

[GiveMeABreak]

The impact may have done more damage than expected - this is the fault code beklow: You may have damaged the parking assistance ECU / or the wiring connector to it.

Fault Code:	U131D
Description of Fault:	Fault: no communication with parking assistance ECU. Information not received on the CAN. The time for recording the fault code is 500 milliseconds.
Conditions for Fault to clear:	Ignition switched off and on again
Downgrade Modes whilst Fault is active:	Semi-automatic parking assistance function not valid
Symptoms:	Loss of the semi-automatic parking assistance function
Suspect Areas:	CAN network Connector Electrical harness Parking assistance ECU

[TecJunkie]

Do you know we’re the parking module is located on the 7 seater? We’re is the parking assistance ECU located?
Thank You
Regards

[GiveMeABreak]

If you have the initial range without visual parking assistance, then it will be in the rear left quarter - possibly inside the left stowage compartment or in that vicinity.

[TecJunkie]

Hi Marc. It’s has the self park system. The Citroen c4 Picasso exclusive. Cruse control still works. Can I disable the front parking sensors to make sure that the fault is in the front.?

[GiveMeABreak]

You can't individually disable the front I'm afraid. It will need a diagnostic to determine the damaged components or provide a clue as to the problem. Post any codes up with you VIN.

[TecJunkie]

Vin VF7**************[VIN obfuscated, can be read by forum staff]

Error code u131d
Says permanent fault.

No coms with parking assistance ECU.

Thanks for the support
Reg

[GiveMeABreak]

Ok, so I've already provided the fault descriptor for this code above, so there's no new codes - but essentially either the impact has damaged the actual parking assistance ECU or the wiring in the harness.

If it was a sensor it would tell you which one was faulty, so I think it's gone beyond a sensor.

[TecJunkie]

Sorted was one front sensor

[TecJunkie]

Anyone know the exact position of each sensor and code is I’m sure I have mixed them up as the self parking is turning to soon. Thanks

[GiveMeABreak]

You must not mix the inner, outer or the wheel arch sensors as they are different parts and not interchangeable.

There's no way for us to tell you which ones you have put where on a Forum. You should of marked them before removing them as they may look identical but are not.

Unless you have the part codes from each in which case put them up here and I may be able to assist. They are 10 digit codes and all begin with 16. There are 3 lots of part numbers for the 3 types of sensors and the rear ones are also identical (Inner Middle, Outer Middle and Wheel Arch) to make it easier.