LOTs of fault codes HELP :)

[Justmee]

My daughters C4 grand picasso 1.6 2014 has a lot of fault codes.

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

The list increased after doing a BSI reset.

I am hoping its a common fault cause all or most or even some of them.

A search suggest the reserve voltage device earth point under the front near side wing & all the fuses in front of the battery.

Suggestions welcome.

ELEC POWER STEERING
U131D NO COMS PARKING ASSIST ECU
C1406 ENGINE OR POWER STEERING CALCULATOR OVER TEMP

BSI
U1F1B LIN FAULT 21
B1003 CONFIG FAULT
U1F00 FAULT EVENT NOT STORED
B180E FAULT IN AUTH HANDS FREE REMOTE CONTROL
B1163 NUMBER PLATE LIGHTING CONTROL FAULT
B1209 DISTANCE ALERT FUNCTION OR ADAPTED CRUISE CONTROL FUNCTION INFORMATION FAULT
U1F41 ABSENCE OF COMS WITH SUPPLIES PROTECTION AND MANAGEMENT UNIT
U1F3C NO COMS WITH DIESEL ADATIVE PUMP
U1F40 ABSENCE OF COMS WITH BATTERY CHARGE STATUS CONTROL UNIT

RAIN AND BRIGHTNESS SENSOR
U1802 VEHICLE SPEED DATA FAULT
U1F1A LIN FAULT

ENGINE
U1333 REVERSABLE ALTERNATOR VOLTAGE RETAINING DEVICE
U1218 INTERSYSTEMS CAN ONE OF THE PAREMETERS PRESENT IN A DATASTREAM SENT BY THE BSI IS INVALID
U1332 LIN NETWORK ERROR OF LENGTH OR PROHIBITED VALUE OF THE REVERSABLE ALTERNATOR DATA STREAM
U1133LIN NETWORK THE REVERSABLE ALTERNATOR IS COMFIRMED ABSENT
U1134 LIN NETWORK NO COMS WITH THE VOLTAGE RETAINING DEVICE
U1400 ALTERNATOR LIN NETWORK REGISTERING OF A FAULT ON THE LIN NETWORL
P2452 MEASUREMENT OF THE PARTICULATE FILTER DIFFERENTIAL PRESSURE PLAUSABLE FAULT BEFORE STARTING

[wurlycorner]

I'd certainly suspect a common issue causing all that, yes.
Either something dragging down the bus networks, or a power/ground issue.
I'd start checking the power/grounds to each of the ECU's that's flagging a code as first port of call - and check that the grounds can actually carry current, not just 'continuity' to ground.

[Justmee]

and check that the grounds can actually carry current, not just 'continuity' to ground.

Yes had that "carry current" issue with rear right abs sensor. Voltage and earth ok on multimeter but fail in use under load.

[Justmee]

Things I have done:-

Cleaned fuses & connectors in fusebox on end of battery
Cleaned earth point in N/S wing for voltage retaining device
tested continuity between alt plug and ecu A plug
Added extra jump battery to ensure voltage was ok (saw video where just doing this stopped all faults)
carried out a forced DPF clean
lots of resets ensuring keyless fob was in its port

Codes now down to:-
U131D No coms with parking assist ECU not charactarised
B1003 config fault
U1F00 fault event not stored in log
B1163 number plate light control fault (must check if lamp lights)
B1209 distance alert function or adapted cruise control function information fault
B1219 fault in the electric power steering status information for the semi auto parking system
P2452 measurement of the particule filter differential pressure pluasibility fault before starting
U1133 lin network the reversable alt is confirmed absent
U1134 lin network no coms with voltage retaining device
U1400 alt lin network register of a fault on the lin network



Half way there lol

[wurlycorner]

Yep - progress.

Which ECU's are the U codes stored in?