Citroen C4 1.6HDi 90 Diesel CRD VTR - Anti Pollution Warning Faulty ECU / HP Pump Sensor

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Thu 20 Jun 2013 19:48
Citroen C4 1.6HDi 90 Diesel CRD VTR - Anti Pollution Warning Faulty ECU / HP Pump Sensor - jimone

Hello All,

I have a Citroen C4 1.6HDi 90 Diesel CRD VTR (59 plate), which recently starting cutting out and displying an Anti Pollution Warning. It was taken straight to the garage from where we had bought the car. They diagnosed the fault as being the HP Pump Sensor, which they replaced and told us the car was ready for collection. Before we had chance to collect the car, they contacted us again to say that the car wasn't fixed as it was still cutting out.

They are now saying that we need to replace the ECU as it is intermittently dropping the supply voltage to the sensor. They are also now saying that they had to replace the sensor first as it cannot be tested separately. It seems to me that they misdiagnosed the fault and are now lying to us to get us to pay for the sensor as well as the ECU. Can anybody confirm whether it is true that the pump sensor cannot be tested separately?

Thanks in advance.

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Fri 21 Jun 2013 13:24
Citroen C4 1.6HDi 90 Diesel CRD VTR - Anti Pollution Warning Faulty ECU / HP Pump Sensor - Collos25

Was this a Citroen agent or a backstreet garage,the first problem is that you need Citroens own computer software to read the ECU correctly its either called Lexia or Planet one for Peugeot and one for Citroen.The most commom reason for the AP warning light is just that an AP warning caused by a number or issues low Eloy level,Eloy cap sensor,choked up EGR valve,choked up DPF.From what you describe the garage unable to get to bottom of the reason for the problem have decided to rewrite the ECU program taking out the AP warning out of the program.I would remove my car and take it to somone who knows what they are doing these are complicated systems and if you do not know what you are doing untold damage could be done.

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Sat 22 Jun 2013 08:16
Citroen C4 1.6HDi 90 Diesel CRD VTR - Anti Pollution Warning Faulty ECU / HP Pump Sensor - jimone

Thanks for taking the time to reply.

The garage is a Citroen dealership, the same one we bought the car from. I shall ask them what software they used to diagnose the problems. After replacing the sensor did not work, they had to bring in a specialist to perform further diagnosis as they couldn't identify the problem.

Regarding the sensor, do you know if it is able to be tested separately? I was thinking of asking them for the original sensor so I could get it tested independently?

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Sat 22 Jun 2013 08:17
Citroen C4 1.6HDi 90 Diesel CRD VTR - Anti Pollution Warning Faulty ECU / HP Pump Sensor - jimone

Thanks for taking the time to reply.

The garage is a Citroen dealership, the same one we bought the car from. I shall ask them what software they used to diagnose the problems. After replacing the sensor did not work, they had to bring in a specialist to perform further diagnosis as they couldn't identify the problem.

Regarding the sensor, do you know if it is able to be tested separately? I was thinking of asking them for the original sensor so I could get it tested independently?

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Wed 11 Sep 2013 17:42
Citroen C4 1.6HDi 90 Diesel CRD VTR - Anti Pollution Warning Faulty ECU / HP Pump Sensor - salouboo

Hi,

I just wondered if you got to the bottom of this problem as I have an 09 Picasso that is doing just the same, It is cutting out every one or two days with this error message then it restarts normally. Your experience may be helpful.

Thanks in advance, Sarah

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