Xantia won't start

[Patonki]

I managed to wreck my xantia by putting the battery leads wrong way
(yes you can laugh) Now the car won't start and lights the yellow key light in the dashboard. Where should I start to look for the resolution or should I just tow it to junkyard?

[CitroJim]

It sounds very much as if you have damaged the immobiliser

What engine does your Xantia have? What age is it? Series one or Series 2? Knowing that we may be able to advise a solution and/or a workaround..

Hold off the call to the junkyard, all is not lost just yet

[Patonki]

It sounds very much as if you have damaged the immobiliser

What engine does your Xantia have? What age is it? Series one or Series 2? Knowing that we may be able to advise a solution and/or a workaround..

Hold off the call to the junkyard, all is not lost just yet

It is 98 2.0 16v and mk II aka facelist model. Thankyou in Advance. I should never tried to install battery in pitch dark in first place

[CitroJim]

Thanks, the first thing I'd do is check all fuses in both the cabin and engine bay fuse boxes.

Then get a Lexia diagnostic machine hooked up to the car and see if it can 'see' the CPH ECU and the engine ECU - or any ECUs at all for that matter...

Any ECUs the Lexia cannot communicate with may have been damaged by the reverse polarity. The fact the orange key (immobiliser) light is on suggests the CPH and or Immobiliser Transponder ECUs may be damaged...

If the Lexia can communicate with the CPH it may be worth trying to re-program the keys..

I can supply some circuit diagrams if needed...

Hopefully you have just blown a few fuses...