Hi all

i have an interesting problem - my S type 3.0 Sport is missing on cylinder number one. Test have shown that there is a direct short on the supply which appears to be occurring in the ECU. The short disappears when the ECU is disconnected. Can anyone tell me if this is repairable or is the ECU toast???

thanks

 

The ECU, or engine control module, is typically re-buildable. You have, however, not indicated the model year of your S-type and (more importantly) your location. If in the States, it is unlikely that you would want to ship your unit off to a facility "across the pond," and the same applies if you are in GB/continental Europe.

Also, you may want to post an :"introduction" in the New Members forum, which is the expected thing and the place where we also go to try to find out omitted details in technical posts (see above).

 

I am based in Her Royal Britannic Majesty’s Realm of the United Kingdom where Jaguars are born - just a few Imperial miles away, in fact. The vehicle is a 2003 3.0l V6 in black with black leather interior and type R wheels, also in black. I have read of batteries being a cause of problems and flooded spare wheel wells, nether of which apply in this case. Any constructive help would be much appreciated and gratefully received.

 

There are multiple repairers - try a web search for such as
PCM repair
ECU repair

However, your era car has a very robust PCM so don't be surprised if it's fine and you have a wiring or other fault.

 

The ECU/PCM in the S-type was upgraded with the 2002.5 model (X202) in GB and 2003 MY in North America. The Denso engine management system that your car is equipped with in generally very reliable (and similar to a Toyota/Lexus V6 unit) and rarely fails. As JagV8 indicates, a bit more investigation may be a good idea prior to packing the unit off for repair, or seeking a very expensive replacement at a Jaguar dealer.

 

The diagnosis has been reached by an auto-electrician he identified the short and then proved it by disconnecting the ECU and the short disappeared. It is an infuriating problem as it is so difficult to get the unit out!!