Hi , Is there any web sites that have a good list of what ECU’s can be used on any XJ40’s. I know that there is specific ones for different countries and different emissions . There’s different color stickers and build date codes on them , can anyone explain what they equate to ? I"m in Australia , so what would the codes be for a car here , Just in case anyone knows what would be good for my cay , 1989 4.0 xj40 ,( an early 4 litre with the 90 dash ) . This is driving me batty , trying to find some answers . Thanks in advance .

 

As far as I know there is a body control module as well as the engine control module - not sure which one would be classed as defective (if indeed that is the issue) and cause your problems ...Have you studied the circuit diagram of the instrument binnacle and it's connections?
Usually the pinning and maxing out of a gauge is caused by lack of resistance in a circuit, so that instead of a regulated or buffered signal you get the whole whack. I've seen this happen to the oil pressure gauge when an incorrectly calibrated (for the 40) aftermarket sensor is fitted without a corresponding resistor "pigtail". There are quite a few of these pigtails used in the Jaguar harness. Could it be possible that one has been bypassed/omitted/broken down? This isn't to say that the pigtail connector is the problem, there are many possibilities including of course a resistance problem inside a component and a dead short to ground.

The Jaguar parts catalog online should help you with identification of parts specific to your VIN and location.

https://parts.jaguarlandroverclassic...j6-xj12-parts/

Larry

 

Lawrence , Thanks for the reply , a bit more research on my part to be done i think . Will sort , one way or another . Mark