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stocktake · 29th July 2019, 17:20

The biggest problem we have on this is the distance and none of us can pop round and sort it

Would be a lot easier with the whole assembly including the RF-150 box were laid out separate from the car.

Still, my initial observations: The fan is not original and appears to be a two or three speed fan that has been converted to a single speed.
My thinking behind this is:
Black is negative
When energised then:
Green slow speed (currently spliced together)
Red medium speed (currently spliced together)
Both high speed
Then again I strongly suspect it could be simply Low/High

So, we can now take the fan wiring out of the equation.

Following the way the resistor is wired the feed from the plug goes to the control box and the circuit through the resistor is made complete when BOTH the relays are energised. this then returns to the plug.
Is it possible that the wiring in the plug then completes the path to the mysterious RL -150 box which in turn sends the power to the fan.

I would suggest that providing the cars wiring has Not been altered upstream of the main plugs then a replacement fan harness with a modification to remove the resistor and not to splice the high and low wires together to go straight to the red and green on the fan.

EDIT: If I Remember correctly the car harness is always live even with the keys removed so care should be taken.
Edit 2: Could it be a 1.8 fan?

29th July 2019, 17:20	#29
stocktake Vis Whiz Rover 75 2.5 auto Saloon Join Date: Jun 2007 Location: LEEDS Posts: 20,591 Thanks: 2,057 Thanked 3,056 Times in 1,621 Posts	The biggest problem we have on this is the distance and none of us can pop round and sort it Would be a lot easier with the whole assembly including the RF-150 box were laid out separate from the car. Still, my initial observations: The fan is not original and appears to be a two or three speed fan that has been converted to a single speed. My thinking behind this is: Black is negative When energised then: Green slow speed (currently spliced together) Red medium speed (currently spliced together) Both high speed Then again I strongly suspect it could be simply Low/High So, we can now take the fan wiring out of the equation. Following the way the resistor is wired the feed from the plug goes to the control box and the circuit through the resistor is made complete when BOTH the relays are energised. this then returns to the plug. Is it possible that the wiring in the plug then completes the path to the mysterious RL -150 box which in turn sends the power to the fan. I would suggest that providing the cars wiring has Not been altered upstream of the main plugs then a replacement fan harness with a modification to remove the resistor and not to splice the high and low wires together to go straight to the red and green on the fan. EDIT: If I Remember correctly the car harness is always live even with the keys removed so care should be taken. Edit 2: Could it be a 1.8 fan? __________________ Dave... Lost a few stones and a Gall Bladder and part of a bile duct and all of my dignity in the suppository incident Last edited by stocktake; 29th July 2019 at 17:56..