Using the ECU error codes
I put this in another thread, but thought I's start one anyways, in the hope of some replies.
I've got an 89 EA 3.9L MPFI, and there is an idling problem with it. I'm putting it down to a dodgy (No1) fuel injector or connection, a MAP sensor problem, or possibly a TPI problem.
I want to access the ECU and see if comes up with any error codes.
I've got manuals to tell me how to do the Key On / Engine Off test, but it refers to using a multimeter or LED to display the ECU output (the codes).
Can I use a bog standard circuit tester to read the codes, or does it have to be an LED?