Check engine light doesn't work

[1yy07owner]

Check engine light doesn't work. Have started checking it out but need to know where the lamp driver is located? Is it in the vicinity of the ecm?

Thanks for the help.
Dan

 

[82ColEd]

Dan,

you got me stumped.. And i dont have access to my books right now..

Try posting on the 82CE board, maybe they got an idea..
http://www.82ceregistry.com/forum/index.php

Stefan


PS: I am assuming you checked that the bulb is ok?

 

[1yy07owner]

Check Engine Light

Yes stefen the bulb is ok. Thanks for the help. Will keep looking for the prob.
Thanks,
Dan

 

[82ColEd]

Dan,

after i got back from Auburn, i got my 82 Shop Manual out, so let's do this one step at a time:
1 - With the ignition turned on and the engine stopped, the CHECK ENGINE light should be ON (bulb Check!).

Is that working ? Or is it OFF ? If so, you got either a bulb problem (not necesseraily the bulb itself, maybe the socket..) or something is WAY strange there.. Then we would have to follow the cabling... But one thing at a time..

Let me know and we'll take it from there.

Stefan

 

[GT6Steve@aol.com]

Check Engine Light

Hey,
That's the one most reliable piece on my car! It's always on, if only I could send it to ya
Steve in Las Vegas

 

[1yy07owner]

Stefan,
With the ignition on. The light doesn't come on.
The only way the bulb comes on is to jumper it on.
The fuse for the check engine light was also checked and good.
Dan

 

[82ColEd]

Sounds to me like the socket for the bulb is either corroded, or the wires going to it are cut somewhere.. See if you can trace out the cables and make sure the socket is ok. Let me know what you find..

 

[Twin_Turbo]

There's an orange lead running from the junction block next to the battery to the ECM. It's the power lead for the RAM (memory) on the ECM. There's a fuse in the wire, check that and check if it's still connected to the junction block (or if there's even 12V on that block). Without it the check engine light won't work, the diagnostics won't work and the "learning" ability (BLM and INT) of the ECM won't work either.

 

[1yy07owner]

Check engine light

Twinnie,
The fuse is good and as far as I can tell the wiring is ok.
Am in the process of taking the computer out to check the harness connections. and wiring.
Dan
Thanks for the help so far......

 

[Twin_Turbo]

Did you probe it for constant 12V?

 

[1yy07owner]

no didn't do that

how do I test for that?

 

[Twin_Turbo]

Just probe between the juction block and a ground or the corresponding terminal on the ECM

 

[1yy07owner]

jumpered the check engine terminal at the aldl and light comes on.

 

[Twin_Turbo]

Does it show trouble codes? Do you have the engine running? If the diagnostics system is working the CEL should come on briefly after ign. is turned to ON pos.

 

[1yy07owner]

Twinnie,
It doesn't flash any codes,nor does it come on whenyou turn on the ignition. Or start the car.

 

[1yy07owner]

Twinnie,
I am thinking the ecm needs replacement....but the car does run fine except for the cel.........
Dan

 

[Twin_Turbo]

what does it do when you jumper tha ALDL with engine off? just burn ? If so, the diagnostics system is dead.. did you check that orange lead for 12V power on ECM? Maybe the fuse in the wire is shot.