Blower problelms

[BX Boyo]

Hi,

I have a 2004 1.9D manual with aircon. My blower failed fully on and I replaced the transistors in the regulator. Both the old ones were shot. However now the blower doesn't work at all! The motor works as I have tested it off the vehicle and the main supply feed to the regulator works. However there are no volts on the other two wires arriving at the brown connector - my guess is these carry some sort of control voltages but I'm loath to apply a voltage without knowing what I'm doing. I have seen references to fuses and relays that might control the power feed to the blower switch and from there to the regulator but not sure what to do next?

Ta

[Ol'Jeffers]

If you're referring to the heater fan speed control I seem
to recall that there are a couple of types. Both are basically
networks of resistors which are switched from the speed selector.
Neither is really expensive to buy from some of the suppliers on
eBay. http://www.ebay.co.uk/sch/i.html?_trksid...&_from=R40

[BX Boyo]

Thanks Ol'Jeffers,

I have the transistor version of the control pack and that was where I started. The blower was stuck on 'full' - so following the wisdom of many threads I replaced the transistors. I got mine from RS - MJ11015G, stock no 6881502 £6.41 the pair. However since replacing these my blower has stopped all together! As I understand it a control voltage is sent to the pcb with the transistors on it and this voltage controls the fan speed. I however can't measure any volts on the 'other' two wires (two thick red and black ones supply the grunt to the motor) to the board and am wondering if a) I have done something terrible or b) there is another fault in whatever is sending the control signal to the fan speed regulator in the first place.

Thanks BB

[Ol'Jeffers]

I hope you were careful when you soldered them in place and you made sure that you had the base and emitter connections the correct way round as they are not reversible.
If the blower was running when you took out the faulty transistors then you should be OK unless the wiring is now faulty or the transistors are 'upside down'.
How did you re-fix the transistors into the heat sink as I believe the originals are riveted?
Personally, I would have replaced the entire unit for 17 quid!

[BX Boyo]

Hi Ol'Jeffers,

You could well be right - I didn't realise I could have the whole board for 17 quid. I think I read the top line of £80 from the dealer.
Mechanically the transistors will only go in 'one way round' - the pins are slightly offset but to be honest I didn't check that the base/emitter was the same as the old ones. School boy error. I've used some M4 bolts having drilled out the rivets and of course there is always the possibility that damage was done in the process. Would you expect the speed selector to be sending out a voltage I can measure to the board, or is it not that simple?

Thanks for the advice. BB

[Ol'Jeffers]

Take a look at this: http://www.ebay.co.uk/itm/644178-AX-Citr...5402e299b1

[Rustscrat]

I'm not familiar with the A/C units but this looks like it's controlled from your temp controller. Looking at it with a dark view, if the transistors have shorted to base then there's a possibility that it could have damaged the the controller outputs.
Don't forget there will be other safety items that will stop the A/C from coming on eg. gas pressure and thermal sensors.
If you want a wiring diagram, P/Mail me your Vin No. and I'll see what I can dig out. :thumbsup:

Update - Have you got the right transistors as the ones you have placed in are PNP (MJ11015G) where as the ones in OJ's link are NPN (MJ11016).

[BX Boyo]

Thanks Rustcrat,

I too noticed the difference in the transistors. I was going off a published fix which specified the MJ11015G, however I have taken OJ's advice and ordered the regulator board from his link. We'll see what happens with that installed. Thanks for your help BB.

[tucker]

Hi

I have done both fixes on my Air con model.

I initially replaced the transistors and fitted them in place with bolts and it ran fine for about 2 years and they went again, so second time around I bought a whole replacement unit.

[Rustscrat]

Here's the diagram for your van.
Item : 8046 - blower speed module
8070 - air inlet reduction motor
8050 - blower motor
8025 - main controller
alut: