Cruise control not working (fix)

Cruise control became 'not working'.

The usual operation would be that sliding the arming switch from off to on while travelling above about 43 MPH the car would emit the 'gong' sound. This warns that cruise control is armed and read to accept inputs from the steering wheel switches.
Switching the on/off switch made no difference, no gong and no control from the steering wheel switches.

Fist job was to connect lexia to scan for faults that may be inhibiting the cruise control.

No (new) faults found so live data was used to monitor the switch input to the BSI. Operating the on/off cruise switch should mirror in the live data but it didn't.
As I operated the on/off switch I could see that the cruise stayed 'on' and decrease in reference would change as the switch was slid from on to off. Pressing the 'SET -' also gave the decrease in reference signal to lexia.

This looks very much like a VAN fault where the resistances are messed up. Its a very simple circuit behind the switches and an inspection did not show any damage so I started with the easy stuff first.
I cleaned the board with some electrical contact cleaner and ran the fiberglass pen it.

Instant results, the switch started switching in the right signal and a test drive over 45MPH gave the 'gong' and allowed the cruise control to function again.


Interestingly lexia has a very deep level of diagnostics for the cruise control system
But this time, I didn't need it

Can you tell how you removed the control plate?
Do you have some pictures of the plate?

Thanks in advance.

daBrown75 wrote: ↑Thu Jun 07, 2018 4:33 pm Can you tell how you removed the control plate?
Do you have some pictures of the plate?

Thanks in advance.

The whole sail shape plastic switch carrier just pulls off and you are left with what is in the picture above.


and this bit (but this is missing the sliding switch).