Did you check codes on A-2??? If you plug in A-2, and then hit the little black button 3 times, that brings up a self test. Part of the self test is to run the fan at low and high speed for 3 seconds.


Thermostat Opens
Starts (2) ............................... 186F (90C)
Fully Open .............................. 216F (102C)
Turbo thermostat starts opening at 180  F (87  C).

Unless you have noticed the instrument panel temp gauge going up, the fan is working OK.

The yellow/white wire from the ECU to the relay is for low speed, the yellow wire is for high speed. Power is only supplied to either when the ECT signals the the ECU that the temp range is too high, around 216F for low speed.
The red wire to the relay is fused and always HOT. The red and green wire to the fan is for high/low speed.

So you need to check the fuse box, somewhere, because you have no power on the red wire.

Klaus

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Two great Volvos, a 1967 220 and a 1998 V70R