Heater blower only works on 4 - 2006 Volkswagen Jetta

Replace the blower resistor. Cheap fix and guys at parts store may help show you how.

1. Check engine coolant.
2. Check heater core.
3. Check electronic control valve.
4. Check thermostat.

The problem lies within one of these four possible issues. =)

The heater blower is normally controlled by voltage sent to the blower via a resistor network.
In this case it seems that this unit also called the fan resistor is defective.
I assume that 4 is the position where the blower is running HIGH and in this position the blower is powered directly without using resistor for lowering the speed of the blower. In step 1 - 3 the blower is powered via the mentioned resistor network.

In my opinion the resistor network is defective.
Replace it !!!!.

look in passenger foot well on blower case for 4 wire connector.



Behind right side of I/P, A/C-heater plenum


resister bad would still allow high speed. may be blower motor.

• The blower motor does not operate/does not operate correctly

• Open fuse.
• Tripped circuit breaker.
• Circuitry open/shorted.
• Heater blower motor switch (18578).
• Heater blower motor switch resistor (18591).
• Blower motor relay.
• Blower motor.

you need to change your blower motor resistor it should be located neer or on the blower motor housing.

I would replace the blower resistor first. its down by the blower motor.

check fan blower relay

Your blower motor resistor has gone bad, it should be located next to your blower motor in the car, held in place with a couple of screws, remove it and replace it. The resistor is responsible for making the blower motor run at slower speeds than high or (4). Let me know if this helps.

You might have a bad speed selector switch, or your blower motor resistor is faulty.

remove the trim panel below the glove box and you will see the blower motor,just to the left of it you will see a 4 wire connector plugged into the case. This is the blower motor resistor,this is what you need to replace.