im going to check the diagnostic codes and am wondering if the jumper wire needs to fused or not.
my book doesnt say it does but i just want to make sure before i go and f^%k up my car!

thanks for any advice!

Unfused is ok...But as a precaution I beleive a fused one should work also...

Um, the function of the jumper wire is to ground the diagnostic lead. (The top-left port of the ALDL connector is simply a convenient ground wire.) A short circuit, what a fuse guards against, is an _unwanted_ path to ground that bypasses whatever the circuit load is.

You do not need a fused jumper, since (even though I doubt it would happen) blowing the fuse would kind of defeat the purpose of having the jumper wire in the first place. But since the diagnostic lead is not a supply wire, just a lead in search of a ground connection, the presence of a fuse would do no harm I guess.

I agree totally..as I wrote...unfused is OK...my trailer simpy stated FUSED would work...not that it was necessary....

AS for the function of fuse...it is to protect from a OVER loading of a particular circuit...which can be caused by several things...Yes one being a "shorting" of the circuit itself...

this may be dumb question of the day but....
do i need to have the key on to check for my codes?

No...

Yes...

ok-

did i miss something or what?????
i did the grounding with the jumper wire and all i got was the 'service engine soon' light flashing.
am i supposed to wait a while, have the car running? what happened. where do the codes come up?

thanks for your help guys.

j

(Don't we have some standardized instructions over in TechInfo somewhere for this?)

Okay, if it'* flashing, you should be on the right track.

What you should be seeing here is a pattern of flashes:

*blink* (pause) *blink* *blink* (longer pause)
*blink* (pause) *blink* *blink* (longer pause)

Count the blinks. Each group will be a pair, that you'll count up for a 2-digit number. What you see here is a Code 12, meaning (when the igntiion is on but the engine is off) that the computer is seeing no tach input signal (which is true, since the ignition is on but the engine is off). On a more general level, what it'* telling you is that it'* now in diagnostic mode and dumping its error codes.

So it will repeat that three times, then go on to blink out whatever other codes it has stored. If you see nothing beyond Code 12, go ahead and start the engine. If no further codes appear, then no errors are stored. (You will _always_ get a Code 12, if nothing else, and that is normal.)

thanks for the quick response. i will try it again.
how many codes can it throw out?
does it just depend on how messed up the car is?
and what is the point of starting up the car when i think the thing is done?

im so full of questions today arent i?

j

ok-
i think i have a 39. that would be three blinks and then nine right?
3-9
3-9
does it repeat them over and over?

thats the torque converter clutch circuit.
that doesnt sound so good.

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