More blower control issues.

[Guest Stormin]

I have went through he archives and found several mentions of the blower control shorting and staying on, even with the key off. Now.....has anyone had the blower control short and when on low speed A/C,it works fine,then on auto or high within in a few minutes it burns the fusible link. This has been a pain in my neck for some now.So much so that I eventually replaced the link with a circuit breaker. Main reason for the breaker is so that my cooling fans are not totally disabled. System works fine on low....just don't turn it up.There appears to be no medium speed.

This may have all started from a plastic bag wrapped around the front fan blade and burning up the motor.

Just curious to others thoughts on this blower behavior. Thanks, Norm.

[Guest Mc_Reatta]

That's definitely not the normal failure mode for the blower module.

Why don't you just replace it?

[Ronnie]

I have went through he archives and found several mentions of the blower control shorting and staying on, even with the key off. Now.....has anyone had the blower control short and when on low speed A/C,it works fine,then on auto or high within in a few minutes it burns the fusible link. This has been a pain in my neck for some now.So much so that I eventually replaced the link with a circuit breaker. Main reason for the breaker is so that my cooling fans are not totally disabled. System works fine on low....just don't turn it up.There appears to be no medium speed.

This may have all started from a plastic bag wrapped around the front fan blade and burning up the motor.

Just curious to others thoughts on this blower behavior. Thanks, Norm.

Since the problem started with the front radiator cooling fan motor, the blower control module may not be the problem. It only controls the blower fan motor that circulates the air inside the car. That module would not be effected by a cooling fan motor burning up.

Have you replaced the burned up motor?

The ECM turns the two cooling fans on and off independently by picking up relays located in the relay center under the hood. The cooling fan motor, the wiring or the relays (there are 3) that control the fans could be shorted, which would cause fusible link A to blow when the ECM commands the fans to go into high speed.

[harry yarnell]

Have you checked for the fan wiring shorting against a hot manifold?

[JalopyBob]

This happened when my 90 Riviera was about 10 years old. The cooling fans would stay off, and the blower motor would stay on even with ignition off. Replaced the ECM and all was good again.

[Guest Stormin]

Thanks guys for the input. Actually when I posted this my plan was to pick up a used module and try it anyway. When the original fusible link went I installed an in line fuse and on high speed it would blow the fuse in a matter of a couple of minutes. When that fuse or fusible link would blow it would take out the cooling fans too. It was my intention with this post to find others who had experienced the same problem.

Since I posted,I have replaced the module and it corrected the problem. I hope that others might benefit from my new lesson. Thanks again, Norm.

[padgett]

Some shorted windings in the blower motor could cause excessive current draw while still operating, a normal blower motor will draw in excess of 10 amps.