The fan relay (engine radiator fan) is located in the foot well of the passenger front seat... directly in front of the seat under the carpet.
https://www.m3post.com/forums/showthread.php?t=1177827 See screenshot below.
Fuse 28 (5 Amp): This fuse specifically protects the cutout fan relay circuit.
Fuse 37 (60 Amp): Located in the glovebox fuse panel, this provides the main power for the engine cooling fan.
Coolant Temperature Sensor: It is located on the thermostat housing. It monitors temperature and sends a signal to the DME to activate the fan.
A quick way to test the fan's health is to unplug the coolant temperature sensor while the engine is running. If the fan immediately kicks on to high speed, the fan motor and module are likely fine, and the fan relay, temperature sensor or thermostat may be the issue.
Circuit diagram is here:
https://www.m3post.com/forums/showthread.php?t=2074912
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