On top of the Cooling Fan Relay Box, it indicates the following relays for the fans:
Cooling Fan No. 1: H270
Cooling Fan No. 2: H272
Cooling Fan No. 3: H270
Now the actual relays that are plugged in are as follows:
Cooling Fan No. 1: H300
Cooling Fan No. 2: EA12
Cooling Fan No. 3: H300
I'm no electrician, so I am not sure if they are compatible. Are they? What numbers are your relays?
I've been trying to diagnose my issue of my milly S running hot when outside temperatures are above 90 F. Below 90 F the temp needle is below the half point which is normal. But at temps 90 F and above, the needle is hovering above half but below 3/4. Needle never gets past the 3/4 mark (like to H).
I'm guessing that if our cooling system has 3 fan speeds (low, medium, and high), the medium fan speed never kicks in. So when outside temps are above 90 F, the low fan speed is not good enough to cool the engine. So the temp needle starts going up, to some point where the high fan speed kicks in to keep the engine from overheating, thus the temp needle never goes above 3/4 on the gauge.
Do you think my fan no. 2 relay is the wrong one or is broken? how would i go about testing it if it's broken?
I'm going to Vegas this weekend and would like to get this issue resolved within the next couple of days. Don't want my car to be running "HOT" the entire trip.