Forum readers

I have 94-ETC

I can not seem to get it to display any codes, current or history. I hold off and warmer buttons for at lest ten seconds nothing happens

The digitial display on the dash works (i.e. monitoring systems, monitored systems ok) but I can not enter DIC mode to access codes. Could this part of the system not be working? How would you check this?


thanks in advance (TIA)

Entirely stupid question- are you trying this with the engine running or not?

the only question that is stupid is one that was never asked.

the reply is the thing that shows one intelligence.

the key can be on or the engine can be running. either way

Let me try and rephrase question

The digitial messege systems displays monitoring systems messeges at engine start up.

However, I can not get into diagnostic mode to display codes, by having key on and engine not running or the engine running.

The off and warmer buttons perform their normal functions.

So I do not think a fuse is blown.

I was wondering if the diagnostic mode can go bad?

Hope I explained it better this time.

thanks

Or, as I've said, stupid questions are easier to fix than stupid mistakes. :)
Additionally, I learned something new from your answer- that the car can be running during a diagnostic. I always labored under the impression the motor had to be off. That said, I didn't think it was a fuse. You state the off and warmer buttons perform normally. Do you have access to another HVAC panel? My reasoning is something internal to the panel is preventing the signal from processing out to the BCM. It's just a theory- a shaky one at that- but I will assume (with the right of retraction!) that is the HVAC is working normally, a trouble code won't show up on a scanner at the ALDL.

update

Took the car on a stone, country road and again tried the OBD1.

I pushed every combition of buttons I could and then pressed off and warmer and it worked like is was suppose to....

So I would imagine there is a loose wire or circuit board or something somewhere and maybe the ride on the bumpy country road jolted it back to life. Or it was locked up. I guess maybe this system might lock up like a regular personal computer in those days would?

I would not even know how to begin tracking the problem down if indeed there was a problem.

Will just hope that it stays working now.

With ODB2 (1996 and later) the OFF and WARMER buttons work by having ignition off, holding the buttons down and turning the ignition to the ON position, NOT STARTING the engine.

With ODB1, I have used the AUTO and the WARMER buttons pressed down and turning the ignition ON, but NOT STARTING the engine. This should work for you also.

Stop by the shop and have a cup of coffee.

http://members.cisbec.net/samait/coffee.htm


Happy Motoring!

With ODB1, I have used the AUTO and the WARMER buttons pressed down and turning the ignition ON, but NOT STARTING the engine. This should work for you also.



Not true.
The diagnostic mode can be entered with the engine off, or running.

How else would you be able to read live engine data parameters and control outputs (like turning off fuel injectors or other similar functions).

If you had to do it with the engine off, that would be useless!

Peteski