cooling fan relay on '92 240

A '92 240 has an engine driven fan so there's no relay, it uses a viscous clutch on the fan shaft which does occasionally fail.

Perhaps:

Plugged radiator Stuck stat Worn fan clutch (if the car has one)

I had a failed fan (I think it is called the auxiliary fan) in front of the radiator/AC condensor on our '85 765T, but replacing the viscous clutch completely cured the symptoms you describe. Ours would flit with the red within a minute of coming to a stop in the Phoenix summer until I replaced the fan clutch. Be prepared to be shocked by the price - almost $100 US aftermarket or about $200 US from Volvo! I went with the after market.

In an effort to improve the operation of our A/C I also replaced the fan a couple years later but didn't really notice a difference. In ours there is no actual relay, only a thermal sensor in the lower radiator hose.

Mike

On the later 240s the relay for the electric fan is clipped to a bracket on the coil. Look for a black relay with 4 round pins.