Why won't fan motor turn off in 94q?

[msscomm]

PB

OK, OK, I went back and changed the link - the page referred to answers both your questions including pictures, the part # and the price has been mentioned so you won't have to use the search function -

Keep in mind Q45tech's warning - you are fixing a symptom causing the Darlington transistor to fail, probably not the root cause of the failure - s-o-o-o-o-o-o, your call based on how long you intend to keep the car and the amount of $$ you intend to invest.

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PB

Here is the thread I believe you're referring to on NICO along with a picture of what your problem might turn out to be if not a simple relay. I believe it's actually a Darlington Transistor - same thing screws up continually w/BMWs - read q45tech’s caution regarding the stopgap fix and the ultimate solution !

zer...13424

Only a $60-$70 part through Joe

Q45tech, once again, gives the definitive answer____________________________________________________________Q45tech / Super Moderator

"cause of the problem is the big silver object in the middle of the picture, "

No the cause of the failure is the motor drawing too much current overheating the transistors causing them to fail, but most do the temporary fix of replacing just the transistors. And buying some time.

Just like the bad fuel pump motor causes the FPCU to fail !____________________________________________________________

[Q45tech]

YEP! Transistors don't just fail [at least for 30-50 years] the failure is caused by over loading them [drawing too much current thru them]. They over heat easily.

When you change the unit and don't fix the fan motor get a spare just in case.

[PoorManQ45]

HEhe, that's why you put a potentiometer in between the motor and the power source . That's fix that problem

[pretzelboy]

The part looks old---from 94 I would bet...thats not a bad run.........

[pretzelboy]

got a new one from Joe--works great........$57 plus $6 shipping--also got the two relays under the battery for active slip/tcs light--hope that works as good.