Heater only works on number 4

[Bluefishface]

I have had to change the heater blower resistor a few times over the past couple of years as the blower would only work on number 4, however this time I have changed the resistor again but the blower still only works on number 4, can anyone shed any light on what the problem might be? I dont think it's the fuse as it wouldn't work on number 4, someone has mentioned a relay, but????????
Thanks for any advice you can provide.
Ash

[Sam]

Welcome to VWAF :)

If you could give me a clue as to the vehicle I'll move this post to the relevant section where you'll receive the assistance you require.

[Bluefishface]

Hi, I have a Passat r-line 2009. Thanks. Ash

[Flash2]

Have you tried temporarily bypassing the little silver fuse mounted on the resistor itself to see if that makes any difference?

[zollaf]

is the pollen filter blocked, causing the motor to work extra hard and thus causing the resistor to fail ?

[Bluefishface]

No I've not tried bypassing the resistor, how would I do that? Baring in mind I'm not very electrically minded.

[Bluefishface]

is the pollen filter blocked, causing the motor to work extra hard and thus causing the resistor to fail ?
I don't know if the pollen filter is blocked but I will check it, I changed it last year so I wouldn't expect it to be.

[zollaf]

had a french thing once, heater stank of burning electrical. fearing a new heater motor i checked the polen filter. blocked as blocked as a blocked thing. new one and the smell cleared up. was only stinky on low power, flat out was ok so put it down to an over strained motor caused by the blocked filter causing the resistor to get too hot.

[zollaf]

but this wont be your problem if it wass changed last year.

[Bluefishface]

I'm wondering if it's a cracked wire in the loom, I just don't want to take it to an auto electrician to find out it's something I could have fixed myself. ����

[RichardSEL]

It's not the resistor as a whole. But the thermistor that sits on top of it that goes. If you've changed the resistor together with the thermistor complete and you've had blow again, then the motor's taking too much current -- usually the top motor bearings are running out of true causing the fan blades to catch the sides.

It's motor out time and investigate the free running of rotor and fan. You'll notice it doesn't spin freely
If you've still got the old resistors you can change out the thermistor on top with a Maplin's part to save you spending VW spares price again. But the new thermistor can't be soldered back into place -- instead a couple of crimp connectors should be used after cleaning the thermistor's leads and putting some sheath on. Otherwise the heat from a soldering iron could heat-destroy the thermistor.

Instead, cut the old one away carefully, and clean the two spiked terminals. Cut the spades off two crimped connectors, and slip one over each spike. Then bend the new fuse tails at 90º and drop them into the connectors, before crimping tightly. You’ll need a RA14Q ceramic fuse as the replacement from Maplins that costs 99 pence. For specification of this item see:
http://www.maplin.co.uk/p/93c-thermal-fuse-ra14q
VW quotes £40.48 for a new resistor pack. A 40 minute job and done!