HI David.
As promised I got round to hooking up a 2.5 fan two wire 2 speed with gold resistor, below are a few photo's of how I set it up and the video to hear the two different speeds.
One refurbished fan new brushes and gold resistor, two wire 2 speed Fig 1
1
One petrol extension loom to aid hooking up the fan to the cars loom Fig 2
2
Cars fan loom/wiring unplugged from the car Fig 3
3
Extension made up loom fitted to the cars loom Fig 4/5
4
5
Fan now set up to be tested and the speeds forced on with the T4 Fig 6
6
T4 plugged in and the fan is forced on in the low speed, in intervals of 3 seconds as per aloud by the T4 Fig 7
7
Fan forced on in 3 second intervals in the high speed Fig 8
8
This was undertaken a few times and the same result you can hear the tow differing speeds quite clearly.
Click the link video for the fan tested off the car.
https://youtu.be/6gDJen2p3-Q
Click this link for the video fan fitted to the car.
https://youtu.be/ZofkZMTmSPw
When the medium was called/forced on it only allows the low speed to run again in 3 second intervals as no medium speed is applicable to the two wire 2 speed fan with gold resistor Fig 9
9
Fan showing the back of the motor and its wiring note the tags have been opened and re-closed due to new brushes being fitted Fig 10
10
SRB2 control box for the 2.5/2.0 petrol engines Fig 11
11