CITROEN C5 X7 COMMUNICATION ERRORS

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Andrew299
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Joined: 13 Aug 2021, 09:11

CITROEN C5 X7 COMMUNICATION ERRORS

Post by Andrew299 »

Hello,

I have a big issue with my Citroen C5 2.0 163HP 2011.
When going down on a long valley in motor break many faults appear and engine stops. After starting the engine, car is in limp mode (I guess) with speed limited to 40km/h, gearbox in D3 only and faults.
Dash shows gearbox fault, engine fault, ESP/ ABS fault, automatic parking deactivated.
If I delete all the errors, cars drives perfectly, has power and works fine.
This happens only when going down on a long valley in motor brake. (Maybe is just a long motor break and valley is the only place where I can test this). I cannot reproduce this any elsewhere.

I have the DTCs but not the description.
U1213
U1208
P1727
P1605
U1208
U1213
P16A0
U1209
P0000
P0472

Most of the errors are about CAN communication with other ECUs and values received incorrectly.
I went to a PSA electronist but he could not find the reason. He verified the connectors from ECUs (gearbox, esp, engine) and clean them, CAN resistance, verified some ECUs parameters but nothing.
We went to a drive test and faults appeared again. He deleted the errors from the gearbox started the engine but errors reapers.
After deleting the errors from engine and gearbox all fine, car works good even with the errors from ESP.
The electronist said that will sent the DTC's to a colleague, maybe he knows something.

Has anyone encountered this problem? Or any idea how to proceed next?
I need help please
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GiveMeABreak
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Re: CITROEN C5 X7 COMMUNICATION ERRORS

Post by GiveMeABreak »

Some of the codes don't come up, but these are what I have:-

U1213: Intersystem CAN network: One of the parameters present in a frame emitted by the ABS/ESP is invalid. Communication fault between ECUs detected for 3 secs
Symptoms: Engine hesitating, cutting out, Lack of power, Starting problem.
Suspects: Engine ECU, Intersystem network

P16A0: Engine: Detection of runaway caused by oil ingestion after stalling. Monitoring that the engine is not racing by burning its oil instead of fuel. The fault is recorded if, when there is no injection, the engine speed exceeds 6000 rpm for 2 seconds; The total turbocharging exceeds 8000 mbars; The mixture is below 1,1 for 0,5 seconds and the engine speed increases by 300 rpm.

Happens when accelerator pedal position is with foot lifted and not at idle.
Downgrade Modes: Deactivation of the traction control, Performance of ESP settings impossible, Deactivation of the pilot and post-injection injections, Deactivation of the request for regeneration of the particle filter from the diagnostic tool, Request for closing of the EGR valve, Deactivation of the EGR function, Prohibition of regenerations of the particle emission filter and stopping of those in progress, Request to switch off the engine immediately, Request for emergency closing of the turbo air cooler by-pass unit, Request for emergency closing of the throttle, Deactivation of taking account of the ESP torque settings, Irreversible deactivation of the vehicle speed limiter (Need to switch the ignition off and then on, in order to make the function available again), Irreversible deactivation of the vehicle cruise control (Need to switch the ignition off and then on, in order to make the function available again).

Symptoms: Engine acceleration at wrong time, Noise, Fluid leak/Smells, Engine hesitating, cutting out, Lack of power, Smoke from the exhaust
Suspect: Engine (Pistons, piston rings), Turbocharger solenoid valve, Turbocharger position copy, Oil trap


U1209: Intersystem CAN network: One of the parameters present in a frame emitted by the gearbox ECU is invalid. Communication fault between ECUs detected for 3 secs.
Symptoms: Engine hesitating, cutting out, Lack of power, Starting problem
Suspects: Engine ECU, Intersystem network/

P0472: Particle filter differential pressure sensor: Voltage too low. Voltage less than 0,3 V for 500 ms.
Downgrade Modes: Deactivation of the request for regeneration of the particle filter from the diagnostic tool
Suspects: Particle filter differential pressure sensor, Electrical harness, Connectors

P1727: CAN engine torque information fault: Value received incorrect.
Andrew299
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Joined: 13 Aug 2021, 09:11

Re: CITROEN C5 X7 COMMUNICATION ERRORS

Post by Andrew299 »

Thank you @GiveMeABreak
Could be P16A0 DTC for the actual failure? And rest of them are because of this failure?
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GiveMeABreak
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Re: CITROEN C5 X7 COMMUNICATION ERRORS

Post by GiveMeABreak »

An issue for example with the ESP system (Wheel speed Sensor) or a CAN network issue will affect other systems. As the electronic Handbrake is controlled by the ESP system - you will get faults with the handbrake and other speed-related functions, like cruise control, speed limiter, hill start assist for example.

More concerning is the oil issues though
Andrew299
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Joined: 13 Aug 2021, 09:11

Re: CITROEN C5 X7 COMMUNICATION ERRORS

Post by Andrew299 »

As I could understand from P16A0, the turbocharger is supplying the engine with oil, and as a fail safe function is to cut off the injection and air admission. Could be this?