Thanks for the wiring diagram. I'm pretty new to testing electrical stuff, would the process be take the switch out and test the pins associated with the wheel? With a working thumb wheel the resistance should change as the wheel moves?

No need to take the stalk out. Just probe the correct pin on the stalk or at the GM3 end and measure resistance against ground and see that it changes reasonably.

I'm looking into replacement wiper stalks to get a price and have found there is two part numbers.
Real OEM has the part number as 61318363669 (stalk without intensive washing).
Anyone know if I can use the stalk with intensive washing button (I know it won't work) if I can't locate the same part as I need.
https://www.ebay.com.au/itm/28465674...mis&media=COPY

Intensive wash is just an extra knob at the end of the stalk. All other functions are similar.

I got a used wiper stalk for $78AUD with the same part number as the original and put it in last night. I now have 4 speeds of timed intermittent wiping. The knurled wheel on my old one wasn't functioning. With the car stationary position 1 is approx 27seconds between wipes, position 2 is 18 seconds, position 3 is 10 seconds and position 4 is 6 seconds. Those times will all become shorter when the car is moving. Although I never figured out the rain sensor issue I'm happy with this outcome. Thanks for your assistance with trouble shooting this one. https://uploads.tapatalk-cdn.com/202...84d6d1e253.jpghttps://uploads.tapatalk-cdn.com/202...5866cd23c8.jpg

Sent from my Pixel 6 Pro using Tapatalk