Heater fan not working

[CMF_nz_aj]

This is not the usual Nissan problem, fan working at only one speed because of stuffed resistor board.

After checking the fuses, checking the resistor board, checking the switch, checking for power at the motor connection and checking motor resistance, I removed the fan & motor.
The fan worked fine, I couldn't find anything that would have jammed it.
I put it back together. Not working again.
Pulled it out, works fine. I then turned the fan around to the same orientation it would be when installed. It didn't work.

I took the fan off the motor. There was a lot of coppery looking dust under the fan & on the end of the motor. I cleaned all this off & blew out the motor.

It all appears to be working fine now.

This was a 1997 facelift with about 180,000km.
Getting the heater switch out is difficult. Need to remove radio first & pull controls down through that hole.

Also note that the fan is supplied with +12V and the resistors & switch work on the ground connection. Resistance varies from about 0.6 ohm on fast to about 3.3 ohm on slow.

Heater fan motor & resistor are all accessable below the glovebox. The glove box does not have to be open or removed.

 

[CMF_deNs]

Thanks heaps for this Bound to be useful for someone in the future. Might even be me!

---dens

 

[CMF_nz_aj]

Stopped working again. Probably worn out brushes, will attempt to pull motor apart at next opportunity

 

[CMF_nz_aj]

To pull the motor out of the plasic housing, you need to leave the fan impeller on the motor. There is one smallish screw to remove from the end of the housing that holds onto the end of the motor. Then leaver between the fan impeller & housing on opposite sides and you'll be able to pry the motor out.
Then there's two screws that hold the end of the motor on & a typical brush arrangement underneath.
There was plenty of dust & debris inside.
The brushes were work but still quite a bit of life left.
The big surprise was how worn the commutator was. There was a good 1mm deep groove worn by the brushes. Looks really bad.
After giving everything a good blow out & clean I reassembled.

Works again. I'll post again if it stops.

 

[CMF_LonePhantom]

Interesting. The heater in my car is only working on one setting (most powerful). Is there a way of fixing the resistor board, or would it be easier just to get a heater control panel from a wrecker?

 

[CMF_turbo march-rolling shell]

heater control panel from wrecker, 2 screws, 5 finger discount

 

[CMF_LonePhantom]

Thanks mate, just as I expected. Unless the missus goes in to labour this weekend I think I will stop off at the wrecker and see if I can get the heater panel.

Cheers.

 

[CMF_Sean]

Heater control panel won't fix your issue LonePhantom.

Your issue sounds like the heater card, and beleive me no wreckers have them or know what they are around here. However, you can resolder the resistor card, mine has it done and that restored full function to my heater/AC system.

Probably be worth your while to pull the fan blower motor out, give it a blast with some compressed air (after you've removed the housing) and then put it back in. You'd be surprised how many bugs can get stuck in the thing..

Sean

 

[CMF_LonePhantom]

Are the parts of the resistor card that need to be resoldered easy to spot? My Dad's a sparky, and we could probably do ourselves.

 

[CMF_Sean]

Its not hard in all seriousness...

If you remove the card, you just need to desolder the (which should be deteriorated) resistor/joint on one of the rails (its the only one on the card) and then cut a paper clip to size. Once you've done that, scrape a fraction of the coating off the rail (VERY carefully as the rails come off the card very easily) and then hold the paper clip in place, solder and a soldering iron later you're done.

Just make sure the solder firmly sets onto the rail and it coats the paper clip securely. You can then chuck it in and see if it works on LV1,2, 3 and 4...

Hope this helps, I can give you a hand if need be or take a picture of mine if you want.

Sean

 

[CMF_LonePhantom]

Is it safe with a paper clip? that wont overload it will it?

A photo would be great thanks if you could. Cheers mate.