Hello, hope somebody on the forum can help before I have to take car to Taggarts.
I have a very nice Jaguar XJ6 3.0 V6 auto 2003.
I had to have the ecu replaced as it got water damaged.
Got a ecu with the same serial and had it programmed. now car will not start, nothing at all starter will not turn so I am guessing its the immobiliser.
I have searched the internet and tried the trick where you reset the immobiliser by touching the earth and positive battery leads also tried the trick where you leave the battery negative terminal off for 30 minutes. I have checked the voltage on battery shows 12.08v doors open and lock via remote. Many thanks in advance

 

Hi,
Not sure it comes from the battery but from what I know, these cars are very sensitive to the battery tension and 12.08 is way too low!

 

Has the car been starting and running since replacing ECU?

If you suspect battery have it tested under load ie monitor voltage drop under

load.

 

Yes ECU had been changed all the serial numbers are the same.