92 Pontiac Cooling Fan Problem

Can anyone tell me what switch causes the electric fans to turn on in
front of the radiator on a 92 Pontiac GrandPrix? It's a V6 3.1L engine
and generally runs okay without the fans however, recently I noticed
that when it was running warmer than usual with the air conditioning
on, the electric cooling fans that help pass air through the radiator
weren't coming on. I'm thinking there's a switch or relay that may be
bad but don't have a clue where that switch might be. Thanks very much
for any help.

John

The "switch" is in the computer. When it determines that the fan needs to
turn on, it will energizes a relay that sends power to the fan motor. The
relay is the first thing to check. The second relay away from the blower
motor is the cooling fan relay. Swap it with the fourth relay (blower relay)
away from blower motor. Turn on the engine and A/C. The compressor clutch
should engage and fan should come on. If not, check the fan motor. If this
checks good it may be the computer or it may be wiring.


> wrote in message
ups.com...
> Can anyone tell me what switch causes the electric fans to turn on in
> front of the radiator on a 92 Pontiac GrandPrix? It's a V6 3.1L engine
> and generally runs okay without the fans however, recently I noticed
> that when it was running warmer than usual with the air conditioning
> on, the electric cooling fans that help pass air through the radiator
> weren't coming on. I'm thinking there's a switch or relay that may be
> bad but don't have a clue where that switch might be. Thanks very much
> for any help.
>
> John
>

Scott Buchanan wrote:
> The "switch" is in the computer. When it determines that the fan needs to
> turn on, it will energizes a relay that sends power to the fan motor. The
> relay is the first thing to check. The second relay away from the blower
> motor is the cooling fan relay. Swap it with the fourth relay (blower relay)
> away from blower motor. Turn on the engine and A/C. The compressor clutch
> should engage and fan should come on. If not, check the fan motor. If this
> checks good it may be the computer or it may be wiring.

Got it - thanks Scott. Appreciate it very much. Turned out to be the
relay.

John