REAR Blower resistor part no ?

[ndrk]

Long story short:
Recently bought Transit Euroline for camping activities. Its a 2004. Based on Tourneo and built by Westfalia.
As usually happens, rear heating/vent system gives different problems. And I got them all...
* Fan is always on full speed, no matter how you adjust it from ceiling knob
* Blows only from lower vents (at full speed)
* Blows only cold

So took rear panels apart and looked at the system. First thing removed gearbox and of course this legendary centre gear is stripped. I put soft rubber washer under it and it works as gear is 2mm higher and from this area teeth are not stripped. Althought the flap itself clicks because gearbox is always trying to push the flap to one end or another. No centre position whatsoever.

As by my research blower motor speed is controlled by resistor. As my blower motor has only one position - full action, im guessing resistor shall be replaced. Took it off but i cant find any part number. Google only offers front motor resistors but they are different. Can anybody help me out with that.

Third thing - Water pipes are cold at the back. Does valve need replacement or can the problem be more upstream?

PS! my front heating acts strange also. It blows hot and suddenly it goes full cold. And it does not matter which position is heating knob. And then suddenly it has hot air again for a while and then its cold again.... cant figure that out...

[Altransit]

Have a search on here for something called a "blend door actuator", this could be the cold/hot water problem

[ndrk]

Thankx for info. Still looking for rear blower resistor part number....

[wojciech]

I enclose two wiring diagrams, which together form the entire rear heating system.

If the fan works only with maximum power, regardless of the position of the knob, then either all the pins of the resistor 1, 2, 3 and 4 have been shorted (the resistor in the diagram is in M211 module), or the pins of the switch (in the diagram P83). The reasons for this are either a damaged resistor or burned out switch contacts.

The temperature knob setting determines whether the airflow is downward, upward or from both directions. The electric actuator (M145 in the diagram) with the toothed gear that you have repaired sets only in three positions - end and middle. This is determined by the double potentiometer in the P83 control module, pin 8, yellow wire. The diagram shows a continuous potentiometer, in fact there are three insulated plates connected by resistors (three electric actuator positions).
Since the electric motor comes to the end and does not stop working and clicks with the toothed gear, the system of the electric bridge of the resistors is damaged. It consists of a potentiometer in the electric motor and a potentiometer in the control module. The electric motor works as long until the resistance of its potentiometer is the same as that set on the potentiometer in the control module. The rear heater control module is one part of the trade and is extremely expensive - in Poland over PLN 2,000 (£ 400). It is sometimes available on the web.

The second potentiometer regulated by the temperature knob (pin 7, green-yellow wire) operates continuously, controls the operation of the electronic module (A264 in the diagram), which sends a PWM signal to the heater's water solenoid valve. Thanks to this - depending on the time of the PWM signal, the valve supplies more or less hot water to the heater. The valve works in such a way that water always flows through it, regardless of whether it is directed to the heater or directly back. Therefore, the water lines connected to the rear valve should always be hot when the engine is warm. If in your van the water lines connected to the valve are cold, then you should look for the cause in the engine compartment.

You can write a 1000-page book about this heating control system in Transit and its failure rate. So in order not to extend - I'm finishing ...