Renault Master II (2006) heater blower doesn't work

[Tomtre]

My Renault Master II 2006 heater blower stopped functioning. The blowing function returned for a couple of times by its' own. The last time for a only a second - when the heater blower was set on the speed 4, but now the heater blower does not function at all.

I replaced the resistor (rheostat?) with a new one but but it did not help at all. The resistor stays totally cold. What is the function of the resistor?

There are 5 wires connected to the resistor. (Some pins in the connector are empty). Could I get more information about the problem by measuring the voltages or currents in the wires?

When I turn the heater blower setting from 0 to 1, I hear a click nearby the fuses under the steering wheel. And a bit louder click from the same direction when turning the heater blower setting from 3 to 4. Do they come from (1 or 2) heater blower relays? Do those clicks tell that the relay or the two relays are OK?

In this situation, what faults are
- impossible
- possible
- likely?

What would be a wise sequence to proceed to get the problem fixed?

Do you have to disassemble the whole dashboard to get an access to the heater blower?

[Paul-R]

Could it be the same as this?

[Tomtre]

Thanks for the video link Paul-R! I don't know if it could be the reason. I should find the corresponding connector in the Master II to check it.

[Paul-R]

The Vivaro is the same as the Renault Trafic but it's worth looking for.