Technical Heater blower unusual failure

[Dadredge]

Last week I inadvertently started my Ducato with the heater blower on max. It blew hard for a second then stopped. Fuse I thought but I had no time to fix that day.

Next day I switched on ignition and the blower worked on 1 and 2. 3 didn't work and neither did 1 and 2 when I switched back to them.

So I don't think it's the fuse but in any case can anyone tell me which fuse it is. The handbook is not clear.

As to my failure I think it must be a faulty switch but can anyone give advice.

(I have read many articles on this forum but none with my specific problem).

Thank you in advance.

 

[Shingy]

The resistor behind the switch seems to be a fairly common cause of blower fan troubles, when it will work on some settings but not others. Just a thought.

 

[taffybloke]

If it is the resistor it usually works on pos 4 only. First check the connector into the resistor as they can play up, un plug it clean the contacts and try again, it could also be a sticking fan.


Mike

 

[Dadredge]

The resistor behind the switch seems to be a fairly common cause of blower fan troubles, when it will work on some settings but not others. Just a thought.

Thanks.

 

[Dadredge]

Update: The resistor looks fine. Main finding is that I have 12v at the plug into the fan! But no rotating fan. Does this mean my fan has failed?

 

[corcai]

Update: The resistor looks fine. Main finding is that I have 12v at the plug into the fan! But no rotating fan. Does this mean my fan has failed?

Brushes might be worn down, if the commutator is ok I've ground some angle grinder brushes when i couldn't get a replacement.

 

[Dadredge]

UPDATE: Removed the fan this morning (what an easy job! One screw, a twist and it's out. No dash or glove box disassembly required). It's dead. Can't see an easy way to look at brushes etc so I will order a replacement. Fingers crossed!

 

[Dadredge]

SOLVED: New fan motor fixed the problem (£108 from local auto parts shop for proper Denso motor which I thought was good given ebay has higher prices for used parts!)

So clearly a fan motor can just fail. The good news is that it is easy to fault find and fix, particularly with the help of this great forum.

 

[digger58]

Brushes might be worn down, if the commutator is ok I've ground some angle grinder brushes when i couldn't get a replacement.

Out of interest what size are the brushes? I buy a good few for older Fiats (wiper motor and headlight etc for X1/9) when in Macedonia, they are all 6x6mm. Very cheap as well

 

[corcai]

Out of interest what size are the brushes? I buy a good few for older Fiats (wiper motor and headlight etc for X1/9) when in Macedonia, they are all 6x6mm. Very cheap as well

In my old van it was something like 5.8mm x 6.4mm so a 6x6 would probably be fine, not sure was it a valeo or denso motor. Local mechanic said 4.5" grinder brushes fit the valeo ones in a lot of cars, doubt he tells his customers that though