Citroën C5 2005 ESP/ASR error

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Citroën C5 2005 ESP/ASR error

Post by phillip77 »

Hello! I bought in the summer of 2019 a Citroen C5 2005 2.2 HDi automatic estate exclusive and one problem has shown up ever since, I should probably start with context: I drive my car for around 30-40 km and at some point it shows me on navi " ESP/ASR defekt" then it shows "System Motorkontrolle defekt." Which translates to "Engine control system defective." I should mention the fact that this car was bought from Germany and it's software is in German. The problem with this error is that the car can no longer accelerate, at most it can maintain it's current speed. What I can do in that moment is to pull over and stop the engine for a few minutes,but then the message "Engine control system defective." Still appears , this time without the " ESP/ASR defekt " . After another 30 km or so , the last message is shown again ,and the car looses it's acceleration ,I'm flooring it and nothing is happening. I am attaching some photos of the errors and the error screen on my tester. I've been to numerous specialists regarding this matter ,but none of them were able to solve it. Please , I need your help, I love this car and I wouldn't want to sell for this error if it's solvable. Thank you very much for your time !

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Re: Citroën C5 2005 ESP/ASR error

Post by GiveMeABreak »

Hi and welcome

The vehicle has gone into a back-up mode as a result of one or more errors. This limits engine power to prevent damage. Switching the engine off and on again may temporarily clear the fault - but of course as soon as the conditions appear that trigger the fault, the same thing will happen again, so you need to understand what the actual fault is. Bear in mind that other systems may also be affected (like cruise control and speed-related functions) if there is a problem with the engine ECU - as they are interconnected, so you may find that curing the main fault will resolve the other issues.

So you really need to get it to somebody with a Lexia Diagnostic kit and get all the fault codes read to get a better idea of the problem.

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Re: Citroën C5 2005 ESP/ASR error

Post by MGmike »

Hi and its nice to welcome another C5 2.2 Excl owner loving the car.

I've had one for the last 16 years, well three actually! The first did 100k miles and was "upgraded" to the second for another 100k and I've just bought a third low mileage example to take on the next 100k!

I agree with Marc... you do need to get a lexia session to see what is actually happening. Turbo overboost is, in a lot of ways, a generic fault which can have many causes and there will usually be other faults logged that a basic code reader won't display. I would start by getting a lexia read out but I suspect the error log may be full if this has been going on for a couple of years. Clear the error log and arrange to have it read again as soon as possible after the next error arrives.

However, there are a few things you can check and eliminate while you find someone with a lexia. Turbo overboost is typically caused by a loss of vacuum on the turbo control valve. Check all the vacuum pipes are intact and in particular the rubber joints at the ends of the rigid plastic pipes. Overboost can also be linked to a swirl valve diaphragm failure which causes a loss of vacuum and is a know failure point. The easiest way to eliminate this is to the block the pipe to the valve as it comes out of the control valve mounted on the engine just to the left of the air filter.

good luck with your investigations.