U1218 on Citroen C5 X7 1.6 HDI

[DinuIoan]

HI guys,

I have a 1.6 HDI C5 Citroen from 2011. My problem is that I saw on my Lexia that everytime I start my engine this error shows:
U1218 - Intersystem CAN.

I can erase it, but it shows up again when I start my engine. What do you think it is?

Best regards,
Ioan.

[GiveMeABreak]

I would need your VIN to relate this code specifically to your vehicle, as that is a communications fault - specifically: Built-in systems interface data not valid fault: Value received incorrect.

What does your interior temperature display read by the way? Let me know the temperature reading and whether you have it in Degrees C or F

[DinuIoan]

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

I have it in C degrees.

Many thanks.

[GiveMeABreak]

Yes, great, but what is the actual temperature showing? I have a reason for asking.

[DinuIoan]

25 C degrees

[GiveMeABreak]

Ok, so this can affect the piloted gearbox. Here is the fault descriptor on your DV6C engine.

So first thing I would check is the electrical connection from the gearbox ECU and then all BSI connectors. If you have had reason to unplug any of these lately that may be a reason - or if you have had any work done lately where the plugs could of been disturbed - that may be worth checking.

Fault code U1218: Fault in the information sent by the BSI ECU - The value received is incorrect. The ambient temperature information on the CAN network is wrong. The time of appearance of the fault code is 10s

Context of appearance of the fault code: Ignition on

Technical precision on the context of appearance of the fault code: Supply voltage correct between 8V and 16V (Pin 3 of the 28-way connector);
Absence of fault codes U1000 - U1003 - U1118

Conditions of disappearance of the fault: The following conditions have to be met;
- Reception of 20 consecutive items of valid information
- No faults for 20 seconds

Down-grade modes if fault present: Default value for the ambient temperature: 20 °C
Switching on of the warning lamp and/or warning message (depending on equipment)

Symptoms: Difficult/impossible to change a gear, Lack of power
Suspect areas: 28-way harness of the piloted manual gearbox ECU
Built-in systems interface

[DinuIoan]

I’ve changed the oil cooler and the thermostat. Maybe this is related. Also I’ve changed the clutch one year ago, but this problem appeared about a month ago.

I will try to have a look at those connectors, as much as I can and know about cars. I don’t have any problems with changing gears or ambient temperature. Hope I will not have any.

Many thanks Marc. You saved me.

[Hell Razor5543]

Might I suggest that, if you are going to unplug connectors, you also spray some contact cleaner into them, to shift any dirt that may have got in (or any tarnish that might have built up). I personally prefer to use Servisol, as I have found it to be reliable, but others may have a differing opinion.

[DinuIoan]

Might I suggest that, if you are going to unplug connectors, you also spray some contact cleaner into them, to shift any dirt that may have got in (or any tarnish that might have built up). I personally prefer to use Servisol, as I have found it to be reliable, but others may have a differing opinion.

Thanks for the suggestions.

[GiveMeABreak]

I’ve changed the oil cooler and the thermostat. Maybe this is related. Also I’ve changed the clutch one year ago, but this problem appeared about a month ago.

I will try to have a look at those connectors, as much as I can and know about cars. I don’t have any problems with changing gears or ambient temperature. Hope I will not have any.

Many thanks Marc. You saved me.

No worries - just keep an eye on things.

[Iankai1]

I keep getting fault code u1218 come up as soon as I delete the code it is back instantly also it won't let start stop activate could anyone on here please help .many thanks

[GiveMeABreak]

@ Iankai1:

U1218 can have different meanings (the specifics are different) so what I have listed above may not be relevant to your 508. You will need to pop your VIN up so I can check the fault as it applies to your vehicle.

[Iankai1]

Thanks the vin is VF3**************[VIN obfuscated, can be read by forum staff]

[Iankai1]

I also now have another fault code of p1a99

[GiveMeABreak]

ok, leave it with me for a few minutes...