Testing fans operation

[morbid]

When I unplug the thermofan switch and jump the terminals the drivers fan goes in fast speed... Shouldn’t it run in slow speed? What may be the problem here?

[9FF]

There are three terminals: a common ground, a fast speed and a slow speed. You must have it jumped between the fast speed terminal and ground, try jumping the other terminal for slow speed.

[morbid]

Originally Posted by 9FF

There are three terminals: a common ground, a fast speed and a slow speed. You must have it jumped between the fast speed terminal and ground, try jumping the other terminal for slow speed.

Mine’s an 84 944. The thermofan switch has only 2 terminals. According to Clark’s test if those cables are unplug from the thermofan switch and jumped, the drivers fan should run at slow speed. And if the ignition switch is turned on, both fans should run fast.

[9FF]

Originally Posted by morbid

Mine’s an 84 944. The thermofan switch has only 2 terminals. According to Clark’s test if those cables are unplug from the thermofan switch and jumped, the drivers fan should run at slow speed. And if the ignition switch is turned on, both fans should run fast.

Gotcha, Im pretty sure that’s normal for the early cars, this may help:

Early Fan Operation - Clarified

[morbid]

Originally Posted by 9FF

Gotcha, Im pretty sure that’s normal for the early cars, this may help:

Early Fan Operation - Clarified

Thank you for that link! Now I’m clear. 🙌🏼