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2003 - Heater Fan Module - Temporary Fix

The Sheriff

Full Member
Joined
Dec 31, 2012
Messages
11
Hi,

I have now replaced the fan speed module twice in the last year and at nearly $200 a pop, transport to the UK; I can't afford to keep replacing it.

The symptom I got each time was the fan continuing to run after the ignition was switched off and it drains the battery.

Question, is it possible to fit an ignition fed relay into the power feed to the unit, I know this will not fix the problem but at least it will stop draining the battery.

If I can where would I fit it and which wires should I break into.

An idiots guide would be great as I am only a moderate mechanic.

Any help or suggestions would be most appreciated.

Why does this module keep burning out ?

Thanks Dave.
 
By module are you speaking of module that the fan motor plugs into
 
The Sheriff said:
Hi,

I have now replaced the fan speed module twice in the last year and at nearly $200 a pop, transport to the UK; I can't afford to keep replacing it.

The symptom I got each time was the fan continuing to run after the ignition was switched off and it drains the battery.

Question, is it possible to fit an ignition fed relay into the power feed to the unit, I know this will not fix the problem but at least it will stop draining the battery.

If I can where would I fit it and which wires should I break into.

An idiots guide would be great as I am only a moderate mechanic.

Any help or suggestions would be most appreciated.

Why does this module keep burning out ?

Thanks Dave.
Chances are that blower motor is pulling too much current.  At least that's what commonly took out the power modules in 1980's GM vehicles.
 
I'm thinking he is referring to the HVAC control,. I could ship the fan blower module to the moon for 200 bucks
 
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Hi, it's the unit that has aluminium blades sticking out of the back if that helps.

 
The Sheriff said:
Hi, it's the unit that has aluminium blades sticking out of the back if that helps.

No picture.
 
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Hope this now works.

If this module is pulling to many amps due to the load from the fan then I guess my proposal above could be dangerous ?

How easy is it to remove the HVAC fan ?

Cheers Dave.
 
no pictures.

Removing Blower fan is easy if you can get under dash on passenger side.
Drop cover. and you can see fan normally held in with 3 screws.
 
The Sheriff said:
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Hope this now works.

If this module is pulling to many amps due to the load from the fan then I guess my proposal above could be dangerous ?

How easy is it to remove the HVAC fan ?

Cheers Dave.
Typical current for the fan on high is 10A-11A @ 14.4V (alternator charging) but motor startup current is much more and who is to say if blower motor doesn't have an intermittent or temp dependent problem that pushes the power module over the edge on rare occasion.  Therefore I recommend replacing the blower motor whenever the power module is cooked.  It's pretty much the only thing that can do this to the power module. Need to treat the cause as well as the symptom (result).  Hope that makes sense.
 
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