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E46 m3 aux fan not working.
If 12v is present then you ve got a bad speed control box on the fan assembly and will need to replace the aux fan.
How the system functions non modulated fans most models through late 90s.
When the fan does not work we could be looking at a faulty fan motor low speed fan resistor temperature switch es low speed or high speed relay fuses or wiring problems.
Just one single engine fan responsible for all the cooling down of that engine bay.
Our initial testing should provide a determination of where the fault lies.
I d suggest you sort out your aux fan if you can not sure how the setup is on the m54.
I run the pusher fan where the stock aux would be located.
You can test that the fan is receiving power with a multimeter you ll want to test between the thicker red and brown iirc wires on the aux fan connector.
31 03 2015 12 02 am oppositelockmt wrote.
If the fan is not operating check the power connector at the base of the fan and make sure it s seated.
If this still fails to turn on the fan i suggest you turn off the engine for now and consider troubleshooting other aspects of the cooling fan electrical system including the low speed fan relay.
Ever since my accident 4 years ago i ve been running without an aux fan haven t experienced any issues what so ever regarding overheating etc.
The n15 design e46 m3 electric fan mount is a great way to add a 16 spal electric fan because it s so easy to install.
The third picture shows what it looked like with the e30 condensor aux fan still installed.
No aux fan on the m54.