front heater fan inoperative

[Bamfman]

Hi
My front heater fan has stopped working.
The fuse under the bonnet looks ok.
If I take a live direct to the motor wire the motor works.
There is no live at the connection to the motor.
There is no live on the connector to the control unit (going in to the section for the speed switch.
any suggestions/help !
Alistair

[g8dhe]

Most likely the thermal fuses / transistor (depends on type of controls) have popped you can either by new modules or re-solder the thermal fuses or replace the transistor which are much cheaper options!
The reasons that the items above blow is usually because the windscreen drain pipe is blocked - centre of windscreen at the bottom pipe drains out under bonnet bay. The water however cascades into the fan when its blocked with the results as seen on this link http://www.g8dhe.net/bongo_images/air_fan_cleaning/
So best first check out the fan itself and clean up also maybe enlarge drain hole in the bottom of the case, then repair the thermal fuses / transistor mounted where the probes are in the picture below;

[Bamfman]

Hi Geoff and thanks for a very speedy reply.
I have had the box off already today and the fan is clean and dry. I had looked at a post from you before I posted re the fuse and saw the picture of the the location but I don't have one on my van. Any other suggestions
Thanks
Alistair

[g8dhe]

The location of the thermal fuses / transistor is where shown but its covered by a plastic cap to keep the water out!
Which type of controls do you have ? The older sliders uses the thermal fuses, whilst the Climate Control electronic variety uses the transistor, they both fit in a module under the cap the thermal fuses are 5-pin and the transistor is 3-pin connector.
Thermal fuses;


Transistor;

[Bamfman]

Hi Geoff
Mine has the slide control. I did have a good look this afternoon and it wasn't obvious. I will go back to it tomorrow and pull a few bit off to try and locate. Under the bonnet is very dry but I noticed it stopped after it had been MOT'd and both front brake pipes had been replaced, so possible they have knocked it when fitting. Will let you know when sorted.
Alistair

[Bamfman]

Hi Geoff
I have removed a component that looks like your photo and is the 5 pin. Not it says "do not try to repair" on it!
I take it you have broken the sides off the one in the picture so you can get to the pins? do you know if you can get a replacement and if so how much?
Thanks again
Alistair

[g8dhe]

Yes its possible that you may need to snap some of the plastic off, but check to see if the pins have melted the solder and sprung up, if so they can be soldered down again, try not to use any new solder, use what is existing as we don't know if its a special melting point solder or standard 60/40 solder. Otherwise the usual spares places do them https://www.bongospares.co.uk/shop/inte ... tor-95-on/ as well as the others.

[Bamfman]

me again
I have put a multi meter on this component and it seemed ok so tested the plug going in to it and there is no live at the plug. is there another fuses somewhere?
Alistair

[Bamfman]

do you know which way the power goes ?
Is it from the fuse to the thermal fuse to the switch then to the motor
or
fuse to switch to thermal fuse then motor?
Alistair

[g8dhe]

The circuit diagram is here, different resistors are selected depending on what fan speed has been chosen;

[Bamfman]

ok not going to pretend that I fully understand the diagram.
have worked out that G1 - 04 is the motor
G1 - 05 is the thermo switch
G1 06 is the fan switch
don't know what G1 - 03 is?
to me the diagram suggested that the power is going from fuse to G1-03 then to the motor which cant be right?
The wire from the heater fuse is light blue/white( L/W) which has the same colour going into the thermo switch so assume that should be main live in. Thinking of running a wire from fuse direct to the L/W on the thermo switch to see if that works
what do you think?

[g8dhe]

The relay G1-03 puts the +12v to the motor to switch on the power to the fan when the ignition is ON, then depending on which resistor is selected from within G1-05 by the selection switch on the control panel G1-06 the fan will turn at the required speed when the selector switch is turned ON.

[Bamfman]

right that sort of makes scene so where is the rely G1 -03 ? that must be the issue.
Alistair

[g8dhe]

The positions of all the connectors is shown on the next page ....

[Bamfman]

Thanks -think it will be later in the week when I can get to have another good look at this problem
Alistair