citroen relay 2012 ecu

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akydawn
Posts: 2
Joined: 29 Dec 2019, 20:25

citroen relay 2012 ecu

Post by akydawn »

hi every one
i bought a citroen relay euro 5 2012 with the engine knackered i replaced the engine but while i stripped the engine bay i never covered the ecu so it was open to the elements and yes it got water logged. the stupidity of me i tried to start the engine and it did for a few seconds then the ecu went dead i have had it tested no signal
any way i bought a ecu,fuse box,bsi and transponder hey presto its started up the issue i have is the back brake lights stay on if i put my origanal bsi unit back in they work as they should but my van wont start because its not programed to the new key and ecu so i have to put the new bsi unit back in
also when it starts up in the morning it has bad diesel knock do i have to get the injectors coded to the new ecu
i need some one who can point me in the right direction as i cant use my van because of the brake light staying on
can any one help please
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GiveMeABreak
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Re: citroen relay 2012 ecu

Post by GiveMeABreak »

Your issue is likely to be several factors.

As you state the BSI, Engine ECU and Key Fob transponders are a matched set. You don't need to worry about the engine fuse box.

However, the BSI is the master computer for all the other ECUs in the vehicle and these are programmed with the correct options at factory for each individual vehicle.

Although you have transferred a matched set from a donor vehicle to your vehicle, the BSI will still be configured for the exact options for the donor vehicle. If anything is different then this can impact on the operation of the vehicle.

What I can do is if you have the VIN from your Van and also the VIN from the donor vehicle, I can check the factory specs of both and compare these. It should tell me what is different between the 2. The added complication is that the Relay vans are available in multiple formats and configurations which may impact on the electrical systems. If you don't have the VIN from the donor vehicle, then the registration will do.
akydawn
Posts: 2
Joined: 29 Dec 2019, 20:25

Re: citroen relay 2012 ecu

Post by akydawn »

hi marc

unfortunatly i bought it off ebay i did not get any identification from the donor vehicle is there another way to check
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GiveMeABreak
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Re: citroen relay 2012 ecu

Post by GiveMeABreak »

Hmm, that might be a problem - but - and I'm assuming that the donor BSI was not changed in any way, it should still have the donor vehicle's VIN programmed into it. Using Diagbox diagnostic kit , it should display the VIN when it connects up. You can check your original VIN as it should be displayed in the lower outside bottom windscreen corner.

It might actually be a lot easier to ring the dealer and ask them if they would be able to download the correct factory options to the donor BSI for you. They will charge you some diagnostic time - but if you explain you have had the engine replaced and the Engine ECU, BSI etc. and can show them your Registration document for the van, and a receipt for the engine / matched BSI you bought (invoice / transaction should still be on your ebay account). then they may do that for you.

I could only tell you the specifications that differ if I had both VINs. - but translating that into the correct parameters in the BSI is not doable without seeing all the options in the diagnostic tool - given the multiple configurations and how the wiring circuits are routed differently according to the type of chassis, windows and door options fitted to these Vans.