I am contemplating changing my ecu / imbolilser module / instrument cluster due to my 2003/ 2.1 petrol auto refusing to start code p1638 .i realise i will need to make sure all these items are removed from the same doner vehicle ,does anybody know if a ecu from a 2004/5 car will be compatible as long as its a petrol with auto box or will it have to be from a 2003 car any information would be very much appreciated.

 

When you do an UPDATE, please continue in the SAME THREAD instead of starting a new one.

The hint is in the word "thread".

Graham

 

Can't find the other thread.

Do proper troubleshooting. Replacing modules is likely to get car to anit-theft lockout and you'll need a tech.

 

https://www.jaguarforums.com/forum/x...-light-226762/

 

I found that one - wrong date, though.

 

It sounds like this happened when you started the car and then quickly turned it off when you relized you forgot something. Then when when came back to start it again nothing happened. Is that correct? If so, did you check the battery? Not uncommon for it to go without notice and if you drained it just enough by starting it and it did not have enough time to recharge to start a second time it could be the battery. If the car was otherwise working well before this incident, the battery is the first thing to check before looking to fix something more complex.

 

Thank you for your reply, yes I did check the battery ,and fully charged it , the only thing that is not working. is when I turn the key to start the car only lights that are on the inst cluster are the oil light, and the air bag light which turns off after a couple of seconds,leaving just the oil light on, but nothing else happens no click ,
nothing but I have noticed the red imbolilser light does not flash at all at any time .Thank s again for your help.

 

If rolling key to on (not start) and the m.i.l. icon (little engine light) extinguishes, that is Jaguar's notice that the immobilizer has been activated.