no codes from ecm

[moosemeadows]

Why would I not be getting any codes from my ecm? When I hook my analog meter to the connectors it shows power because the needle sweeps up but doesn't pulse at all. The emissions lite in the dash is off but lites up when I go to start the truck. Oh by the way it's a 93 explorer 4.0 in a 87 bronco ll. The motor has a slight miss at times like it's dropping a cly every once in awhile. Any ideas?

 

[trashtruck]

can you get codes using a paper clip or jumper wire?

 

[natenkiki2004]

Are you sure you have the connections right?
http://www.explorerforum.com/forums...nd-3-digit-trouble-codes.160035/#post-1483871

Personally, I prefer the jumper method, on that diagram, connecting pin #2 to the STI connector. Doing that will flash the check engine light with your codes.

Obviously, if yours runs, the computer is healthy so there's gotta be a minor connection or wiring issue as to why you're not getting codes.

 

[moosemeadows]

Are you sure you have the connections right?
http://www.explorerforum.com/forums...nd-3-digit-trouble-codes.160035/#post-1483871

Personally, I prefer the jumper method, on that diagram, connecting pin #2 to the STI connector. Doing that will flash the check engine light with your codes.

Obviously, if yours runs, the computer is healthy so there's gotta be a minor connection or wiring issue as to why you're not getting codes.

Yes I'm sure that I've got it hooked up correctly. It did do it one time then it hasn't. I'm thinking it's a wiring issue. Any ideas as to were to start looking?

 

[natenkiki2004]

I guess I'd trace those pins back to the ECM and backprobe there. The computer HAS to be on and responding otherwise it simply wouldn't run.