Citroen C5 2.0HDI 2016BlueHDI 150 Engine Repair light

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tony42
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Re: Citroen C5 2.0HDI 2016BlueHDI 150 Engine Repair light

Post by tony42 »

:clap: Your a saint Marc , at the time I had ran in and looked at a few youtube videos and got no pointers. Further update Oil not changed spoke to independent Citroen dealer who don't have up to date diagnostics. Suggested main dealer. I was out driving at the time and the fault light had returned hence I sort of gave up the ghost.

I got a eureka moment rethinking what Marc had said about the Euro6 and the fact this is an old engine basically with the new emissions crap bolted on. He mentioned something about the new fix's then possibly causing unintended consequences. I thought about that and even though I hadn't changed the oil today I wondered if I reset the service interval and clear codes would that do the trick. For the moment that seems to have done the trick. Car is running fine no fault lights. I drove it out onto the motorway and headed down to Wicklow and then came back all between 2-3k revs. Will change the oil/filter tomorrow. It has only done 9k since oil change but my intention was to do max of 10-12k before changing anyway.

My educated bodger guess on this is as follows: Engine oil appears fine it is not smelling of diesel and the level is normal. Assuming harnesses and connectors are fine I think the issue is down to my driving pattern which I am guessing is not long enough for proper regens. As per Marcs suggestions I am thinking that the ECU parameters are set to fire a warning if X amount of incomplete Regens have occurred over a period of time. I was able to clear the fault for approx 10 days but that was after going for a good run down the motorway. I then reverted to my covid limited commute times and I am again guessing that brought the parameter back down to the fault stage.

The alternative problems of the listed ones from the fault code are Engine oil,Electrical harnesses,Connectors,Particle filter differential pressure sensor and additive pump pump. Not sure if there is a way of testing the pump? Will check out how long the Urea/Adblue should last and my hope is over the next couple of thousand miles it calls for more additive as that I think would rule that out.
The particle filter differential pressure sensor again I do not know if that is possible to test. Don't know how to do it either but will search it out. Maybe fingers crossed it is not mad expensive and if so would change it out as a precaution. Ruling out the oil as I don't think there is any sensor indicating oil viscosity is shot and visual inspection shows its fine (will confirm when I change it out).

Fingers crossed this is sorted and it is just an issue with parameters in the ECU. I will report back how things go over the next few weeks. (again hoping that I will not be back tomorrow with egg on my face reporting the light is back on :oops: )

tony42
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Re: Citroen C5 2.0HDI 2016BlueHDI 150 Engine Repair light

Post by tony42 »

Belated reporting but was waiting to see what if anything would occur since I cleared the fault. Good news is no re-occurence and the Adblue warning came on last Friday. Usual message 2.4k before engine will not start. Fingers crossed I got 10L of Adblue and it took it all. So no problem with adblue pump which was one of the suggestions on the fault code. I can never be 100% certain but my guess on the ECU algorithm identifying regens not completing and if met fire up a warning that the oil is contaminated is a good educated guess. I would be interested to hear if anybody else comes across this problem.

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GiveMeABreak
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Re: Citroen C5 2.0HDI 2016BlueHDI 150 Engine Repair light

Post by GiveMeABreak »

Nicely done Tony.