Heater fan working only in 1st and 2nd possition

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karoliens
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Heater fan working only in 1st and 2nd possition

Post by karoliens » 03 Feb 2013 12:22 am

So my heater fan works only in 1st and 2nd possition and when I turn 3rd it stops. What could be the problem? I read that heater resistor could be broken but where I could find it? I tried to take out this turning switch itself but everything seems find there. By the way how you change cigarette lighter lamp. I took out plastic cover with cigarette lighter itself but then can't reconnect wiring to as wire is such short.

Dean
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Re: Heater fan working only in 1st and 2nd possition

Post by Dean » 03 Feb 2013 01:10 am

I may be wrong but I'm sure the heater resistor is bad only when the fans are not turned to maximum (so anything but 4).

It may be the switch its self.

Don't really know about the heaters because mine has none!

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Speedy88
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Re: Heater fan working only in 1st and 2nd possition

Post by Speedy88 » 03 Feb 2013 01:52 am

Heater resistor I'd say. Easy way to find out is, turn the fan to position 3 with ignition on, take resistor out and touch the three input wires to the 1 output wire until you get max fan speed. This proves that there is no break in the circuit and that the problem exists within the resistor.
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Evoman
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Re: Heater fan working only in 1st and 2nd possition

Post by Evoman » 03 Feb 2013 11:30 am

I have this issue too, it happened at the same time that the fan got stuck. I should find a resistor :)
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mac
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Re: Heater fan working only in 1st and 2nd possition

Post by mac » 03 Feb 2013 09:49 pm

Don't forget that on "full" speed the heater fan does not take power through the resistor but directly via a relay (located under the dash). It is most unlikely the resistor pack is at fault - in fact if the lower two speeds work ok the resistor must be working. If only full speed is absent the fault must be in the feed to or from the relay or in the trigger feed from the fan switch. Check fuse 12 (full speed). Fuse 19 guards speeds 1, 2 and the trigger for speed 3 relay.

Look at the circuit diagram - all will be revealed.

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Re: Heater fan working only in 1st and 2nd possition

Post by Evoman » 03 Feb 2013 10:43 pm

mac wrote:Don't forget that on "full" speed the heater fan does not take power through the resistor but directly via a relay (located under the dash). It is most unlikely the resistor pack is at fault - in fact if the lower two speeds work ok the resistor must be working. If only full speed is absent the fault must be in the feed to or from the relay or in the trigger feed from the fan switch. Check fuse 12 (full speed). Fuse 19 guards speeds 1, 2 and the trigger for speed 3 relay.

Look at the circuit diagram - all will be revealed.

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Haha, thanks Mac! thats helpful. Dont worry, we wont say anything, I hope you're recovering
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karoliens
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Re: Heater fan working only in 1st and 2nd possition

Post by karoliens » 08 Feb 2013 12:43 pm

Than you I would check everything. But where is resistor located exactly? Behind fan switch?

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Speedy88
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Re: Heater fan working only in 1st and 2nd possition

Post by Speedy88 » 08 Feb 2013 12:54 pm

Under the bonnet and under the heater box top cover :)
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karoliens
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Re: Heater fan working only in 1st and 2nd possition

Post by karoliens » 08 Feb 2013 01:02 pm

So I need to remove front heater box cover? All these clamps? Because some are pain to get to.

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Speedy88
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Re: Heater fan working only in 1st and 2nd possition

Post by Speedy88 » 08 Feb 2013 01:03 pm

No just the cover on top, should just be clipped in. Might be 1 or 2 screws I can't remember. It's really easy to take off.
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Re: Heater fan working only in 1st and 2nd possition

Post by Chris_C » 08 Feb 2013 11:04 pm

Speedy88 wrote:No just the cover on top, should just be clipped in. Might be 1 or 2 screws I can't remember. It's really easy to take off.
On a mk2 box, a mk3 is a "take the entire box out" job then undo the clips.

Do the test for the bit Mac talks of first, if 1 and 2 work, it's not your heater resistor.
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karoliens
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Re: Heater fan working only in 1st and 2nd possition

Post by karoliens » 12 Feb 2013 06:16 pm

Thank you very much. The 3rd possition is now working. It was connector at the relay not making good contact.

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