You are experiencing a latch condition any time the fan is turned on.
You need to find out what is likely miss wired by process of
elimination.The models with AC have a 3 speed fan system tied into the
AC so that is the most likely source of the problem. I would remove the
relay for each of the higher speeds one at a time and see what the
result is. Once you know which circuit is the cause you can trace a
couple wires back to the source.

Mark

Bruce Nadig wrote:

> Howdy From Texas,
>
> I've been off the list since mid-December - out of town and away from
> e-mail. I've missed ya'll. It is good to be back.
>
> I have an unusual problems on my '87 GL. The "radiator" fan will turn on
> when triggered by the thermo switch or the a/c, as it should. However,
> once
> it comes on - and it has always come on in the high speed mode - it stays
> on, no matter what. It will stay on until the there is no more power
> available. It will run long after the ignition has been turned off.
> The fan
> runs until it drains the battery or until the battery is disconnected.

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