Overdrive solenoid switch not working

[Martec]

Hi,
After 18 months of inactivity I serviced and MOT-ed our MkII, and half way round our first run out the overdrive stopped playing. Having checked all the usual things, gearbox oil level and power getting to the solenoid, and the operating arm to the solenoid apparently working ( I was underneath but no engine running) I found the solenoid resistance was 10.7 ohms. I took the solenoid off and tried the change over switch, no change.

As this is probably the original I took the rubber cover off and unscrewed the plastic cover and found the change over switch dirty, a clean with very fine Wet and Dry paper and I now have 0.5 to 0.7ohms changing over to 10.7 ohms, ie pull in coil and hold in coil.

Hopefully it will work when we get a reasonable dry day.

I hope this maybe of help to someone.