General 2016 Fiat Ducato heater only works in position 4

[eetsteamleader9101]

I'm sure this has been asked before but struggling to find a post.

I'm in Spain and the heater has decided to only work on position 4. I am pretty sure this, like other cars, is the resistor matrix faulty.

Not sure where it is located, any help much appreciated.

Also apart from main dealers where can i get one in Spain, namely, Alicante, Murcia or Malaga areas.

Thanks in advance of any help

 

[Anthony489]

Hi. In position 4 the speed control resistor is bypassed, so your diagnosis is correct. The assembly contains a number of power resistors and a small thermal fuse which goes open circuit if the temperature gets too high. The mounting is under the dash and within the heater trunking, near to the blower fan. These devices rely on being sited in the blast of air in order to keep them from overheating.

 

[Communicator]

The heater fan speed control resistor is inserted into fan outlet, so that it is cooled by the airflow.
As you may be aware the fan is located under the dash, of which you may have to remove part for access.

(At this point Anthony489 posted above, but I will continue.)

The resistor will have probably have 4 way connector, and will have 4 wires attached.

The attached diagram relates to my 10 years older x244 model, but should give the general perspective.
1. Unlug (There may be a release catch on the connector.) 2. Remove screws (one or two). 3. Remove resistor.

As you need a matching resistor, if you can manage to remove the resistor, and can manage without the heater take it to a motor factor as a sample.

 

[the green vanper]

You have not mentionned which engine does you van have, nor if it has a manual A/C or the automatic one (or none), which COULD make a difference in diagnosing and documentation.

 

[RS3100]

I've previously saved these on a "just in case basis". The first from another forum is pretty self explanatory. The second is unfortunately in several parts as I saved the screen grabs as consecutive images. It's a service bulletin for 2014 onwards vans, relating to a revised wiring loom and relay switch for the fan control.