c5 2.2 HDi 173

[mooseshaver]

This is tricky as I don't have access to my car at the moment, and don't remember the exact fault code.
My new to me 57 plate C5 developed a fault on the way home from the garage and has been stuck at a main stealers for 11 days so far.
When the lights are on, it will often come up with automatic headlights disabled/fault (they are directional). I can get it to do it every time if I turn them on and floor the car, but will come up on their own eventually with normal driving.
Then the power steering will often fail (these cars are so hard to park without assistance!)
also ESP fault.
When I looked on the Lexia all the faults said they were caused by another fault and they had trouble with the engine speed signal. And there was a fault on its own relating to no engine speed signal.
Has anyone come across this before? The Citroen Master Technician can't work it out. All I know he has tried a new fuse box, which did not work.
I'm so desperate to get my new car back.
The garage I purchased it from have been great, they are hundreds of miles away, but are sending the car I traded in back up so I can use it until mine is fixed! But its going to cost me up to £250 to temporarily insure it! (28 days)

[cachaciero]

O.K just my 2 penny worth thinking out aloud as it were.

The injection system needs engine speed and there is a sensor on the flywheel usually which detects TDC (or something close) and from which engine speed can be derived, this signal will be processed in the injection ECU and from there posted out on the CAN bus for anything else that needs engine speed.

Now without a good and valid speed sensor the ECU wouldn't be able to run the engine but the engine does run and apparently well, ergo the signal is present at least to the engine ECU. So it would appear that the ECU is not processing the data and posting it on the CAN bus, given that this ECU produces a lot of other data which is (presumably) getting out on the bus it would appear to be unlikely that it is hardware which only leaves software.

Suggest that it might be a good idea to re-load the injection ECU data, however this might not be so easy, from my limited experience Lexia won't allow you to overwrite the existing data with data at the same rev level only newer so if your ECU programming was upto date i.e no newer version available this could be a problem, sure there must be away around this problem but I don't have it.

It might also be worth checking that other data that the engine ECU produces is present on the CAN bus such as Torque, this to be sure that there isn't a bigger problem with the CAN bus which may be hardware related.

I do wonder what would happen if there was a "hole" in the can bus between the Injection ECU and the ABS /ESC system, don't know if it's a straight CAN Bus link or if it goes via the BSI.

cachaciero

[Lighty]

I had a canbus "drop out " on a C5, just like this, the wiring harness had rubbed through on the front bumper, where it goes to the power steering pump. The pump is just behind the bumper on the drivers side, and the wiring rubs nicely on it at that point.
I would suggest bumper removal (very easy) and check this wiring.

[mooseshaver]

No update so far, the info provided was passed on, but I don't know how that was met.
Thanks anyway.

[mooseshaver]

Small update, they now think its the ABS box.
I'm assuming thats a computer. I don't understand how that fits in with the engine speed?
Are there circuit or block diargrams anywhere that I can read?

[cachaciero]

Small update, they now think its the ABS box.
I'm assuming thats a computer. I don't understand how that fits in with the engine speed?
Are there circuit or block diargrams anywhere that I can read?

The ABS box is an ECU and it will be on the CAN bus so if there is a problem on the bus interface circuitry it could pull the bus down, personally given Lightly's experience I would have expected them to have disconnected every box and checked the CAN bus for continuity and lack of shorting to earth.

I don't have anything S2 specific but I do have a lot of info on S1 and I doubt that there is much difference in this area, if you send me a pm with an e-mail address that will take large attachments I can send you what I have.

cachaciero

[LD]

It's now over a fortnight since this post – any further news? Have you got your car back yet?

[mooseshaver]

Ha ha ha. Going insane with this.
Its five weeks today do far. I was told it was ready on Monday, but that they needed to sort an invoice and won't let me take car without payment.
Tuesday the people that I bought it from (who are paying for the repair) had still not recieved the invoice. At 5:30 I called the dealer, who claim to have sent the invoice, but as of today invoice has still not arrived at its destination.
5 weeks. Five long weeks.
I don't know whats been going on, but will post back when I get the car back. So far I know they have replaced 2 ECUs. One is the headlight ECU. Don't know what the other is. Its also had an entire new headlamp unit, not sure which side.

[mooseshaver]

Just got the car back!
Only one ecu changed, the caclulator.
And the headlamp ass.
The esp fault appears to have been fixed with "carried out diag with lexia cleared & returned, downloaded % configured ecu's"
no mention of power steering, but it didn't go wrong and I had the lights on and turned corners and everything.
Really happy its back. la la la

[jgra1]

good news !

[cachaciero]

Which ECU? calculateur is french speak for computer aka ECU, would be interesting to know just for curiosity's sake.

cachaciero

[mooseshaver]

Spoke too soon. Second start of the car and ESP fault.

[mooseshaver]

Which ECU? calculateur is french speak for computer aka ECU, would be interesting to know just for curiosity's sake.

cachaciero

Headlight ECU.
part C6224R6 £113.12 ex vat

C620846 Headlamp Ass £1132.27 ex vat

[mooseshaver]

Quick look at Lexia before it goes in tomorrow
under BSM we have Permanent fault + ignition on relay

under ESP_MK60 we have Remote fault Permanent fault (which has "Fault caused by another ECU")
then BSI functional, engine ECU operation, No Communication with engine ECU, Auto gearbox operation.
under suspension P05E0 sensor power supply missing
and Permanent fault No communication with the steering wheel angle sensor incorrect value received

Under GEP we have Remote Fault Temporary fault Engine status information no signal
which has a code U1108

under the directional headlamps we have Remote Fault Temporary fault dialogue with the injection ECU no communication.

In the general faults there os F9B7 + ignition on relay, and FBC1, FBC2, FBC3, FBC0 which are parking sensors
also 9651 supply voltage not defined. D308 Engine ECU operation and D108 No cummunication with engine ECU no signal
7362 Passenger's airbag deactivation switch LED not defined
Lots more d308. assume that as it displays reverse chonological order these faults at the bottom are most recent?

[LD]

C620846 Headlamp Ass £1132.27 ex vat . . . that's 1358.72 with VAT at 20 percent . . . for one headlamp unit?! I believe yours are directional headlights, but that's crazy. I thought it was bad enough that Mercedes' price for a heated wing mirror on a C220 is £300, but . . .