Your fan is powered by the ecu thru a Transisitorized pulse width modulated controller located on the driver fender. It feeds the power to the motor and starts out about 4 volts when measured by a voltmeter.

Please treat the control module with the high dollar respect it deserves.

Your fan motor should have a low reisitance, I have not measured it but estimate that it should have less than 5 ohms of resistance. Jumpering the fan to 12 volts will not get you any data cause your fan runs for a while.

Hook up a voltmeter, tape it in and drive around till it quits.

Got voltage ??? motor is bad

No voltage ?? Module and drive circuits are bad ( driver fender )

Woody