XK8LS1

Hello LS community. I am Ron from Lake Dallas Texas in need of advice on a connectivity problem with my ECM.

I did an engine swap (LS1) into a 2000 Jaguar XK8. The car runs and drives but I can't get the computer to connect with the code reader.

ECM and harness are 98 - 02 GM Vortec. Dedicated battery hot to pin 16. Dedicated ground to pins 4 and 5. All check out with low resistance and 12+ volts on pin 16. The serial data line (ECM pin c1-58) to code reader pin 2 seems to be the problem. It has high resistance when connected to the computer and < 1 volt. Off the computer ohms are 0.4.

I checked MAP sensor and A/C pressure sensor lines for 5 volt reference and both were 4.97 volts.

The code reader powers up and searches for the car's protocol but gives "link error" message. Code reader works on other cars. Other code readers give same link error message.

I have switched serial data lines twice and changed computers with same results.

Any suggestions would be welcomed.

Is it possible to get serial data from another 5 volt reference pin out on the computer?

Hope someone has an idea.

Ron

EFIHARNESS

C1-59 is also serial data, not used in many apps.

XK8LS1

I just tried moving the serial data line to C1-59. Unfortunately, same results.

Any other suggestions?

XK8LS1

I am not sure what the problem was, but I tried a third scanner and it worked.