Heater not working

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airborne_7
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Tue May 18, 2010 11:29 am

Hi guys need help,

my heater fans dont seem to work past setting 1, you can feel a slight breeze but nothing like it should be,

Can anyone tell me what the problem is? And what i need to do to fix it?

Thanks steve
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Brianmoooore
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Tue May 18, 2010 9:18 pm

This seems highly unlikely! Are you sure the 'slight breeze' isn't just being caused by the forwars motion of the car?
The speed of the fan is controlled by a series of resistors - the slower the fan, the more resistors that are switched into circuit. In the full speed position, the resistors are switched out of circuit altogether, so when the resistor pack fails, you get the common 'fan only works on position 4' fault.
Sometimes the reported fault is that the fan only works slowly, and only on position 4. This is because the fan bearings have almost seized, and the resistor pack either cuts out or is destroyed by the excess current on the other switch settings.
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lawriejones
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Tue May 18, 2010 9:35 pm

Try a new resistor first and foremost. Easy enough to replace and fairly cheap too.

Its probably located near the bulkhead, access via passenger side footwell.

Failing that, possibly a new switch, although you can test the switch by removing it and using a multimeter across all the pins to see if you get continuity when you select each setting. I tried it and it worked a treat, and believe me, i'm no expert.

Good luck!
airborne_7
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Tue May 18, 2010 10:18 pm

Top man that exactly what i needed il give that a bash! Where can you get cheap replacement resisters from?
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Brianmoooore
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Tue May 18, 2010 11:41 pm

Resistor pack isn't used when fan is at full speed position!
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