Added edition 2014
To get us started i am hoping or presuming you have the original diesel contol box and wiring as below here.
Take note of the purple wire as this will be obsolete later and cut out
Also take note of the thick brown wire top right in the control box this to will be cut out later.
Here we have the petrol two wire 2 speed fan with red and black wires coming from the fan motor.
This is a quick snap shot of what we are aiming to achieve once all the wiring as be changed and cut etc.
The red wire form the fan will join up with the thick brown wire from the plug end this will become clear later.
As you can see here i have left a little of the brown wire so we know what it needs to attach to later, i dont always do this but on this occasion i have.
Now we turn our attension to the black wire coming from the fan motor as here below.
The black wire further down the line from the fan motor splits into two as here in this picture, note where i have made the cut after the joint.
The adjoining black wire will go to one end of the gold resistor picutre below.
The next step is we now pay attention the the diesel control box from our car remove the thick brown wire from the right relay the one the grey wire is also attached to, disregard the black wire for the moment as i am infront of myself in the photo
With the thick brown wire removed from the male spade follow it back and through the rubber bung in the control box and cut the wire.
This wire will now be joined to the thick red wire coming from the fan motor as here below.
Now you know why i left the little brown wire coming from the red wire earlier on.
Crimp or solder these wires together making sure you have added heat shrink before doing so. it can then cover the join and help with water proofing it.
The other thick brown wire in the control box whcih is attached to the large relay will become our black wire later on follow it through the rubber seal in the control box wall.
keep following it until you come to the split joint all this is much clearer as you would have removed the out sheath covering all these wires
At the joint/split cut the wire close to the join, you can see from the photo below i have added a little black insulation tape so we now know this wire will become a black wire very soon.
We now go back to the contorl box and deal with the thick black wire with a thin black wire joined to it, pull this off the male spade and move it to the next relay the one with the grey wire on and fit it to that male spade and relay, htis is here we moved the first thick brown wire from, at the same time take this oppotunity to cut out and remove the purple wire as this is obsolate, cut it close to the rubber seal as possible
Now follow the black wire back to where it joins and splits into two on the main loom.
The loose black wire which was originally attached to your old fan motor one of the four, you cut this but leave at least 4" showing from the joint.
This will now be joined to the thick brown wire which had the little bit of black insulation tape one and the brwon wire which is connected to the large relay in the control box.
Remembering to add the heat shrink before crimping or soldering the joint this as now turned the brown wire into a black wire in the control box on the large relay.
Now look at the red wire coming from the contol box trace it through the rubber seal.
Cut it to length and join it to the thick black wire that splits into two one going to the fan motor the other going to the resistor not forgetting the heat shrink as always.
The last wire to deal with is the grey wire this joins to the other end of the gold resistor'
This as i say joins to the gold resistor i have added a bit of black wire coming from the resistor as in these photo's below.
The final job in the control box is to remove the first thick brown wire we cut as here the one not joined to any relay in the control box.
Take care and make sure you are cutting the right wire cut close to the rubber seal.
Your diesel control box should now look like this job done.
All that remains now is you refit the sheathing refit the fan to the cowling plug it into the main loom, then test it by switch the ignition to II and press the demist button, low speed should run continually.
Any questions please let us know cheers Arctic.