partner demister

[bailsthestud]

demister runs full speed constantly when switch is in any position, please help?!

[bricklayer]

this is a well known fault on the partner and berlingo.....

i am sure if you google it there will be some advice with images on how to sort it....

but here goes my version

look under the dash above the footwell on the passenger side ( sort of behind and above the glove box area) there is the fan, remove theducts and then the fan and you will find an alloy block mounted to the fan housing, on the alloy block there are a handful of transistors a relay and some other electronics, this is the fan speed controller, the alloy block has fins and a cable plug.. this little alloy block contains the problem...

you can buy the alloy block with the transisitors on from a dealer as a replacemet but you are looking at about £90 plus vat for the part, or you can just change the two transisitors over - these cost about £5 each...

there are two transisitors fitted to this controller alloy block- replace both, if you just replace one the chances are the second one will fail once the new one is installed...

this alloy block is seperate to the rotary switch on the main centre dash console...

the large transistors mounted to the alloy block can be replaced- you need to be careful and handy with a soldering iron but it can be done- the transisiotrs can be bought from RS trade counters from a good maplins store or from farnell on line.....

its an awkward job but its relatively straight forward once the fan is removed from the car...

good luck