Jebjerg

I am trying to make my cruise control work (again?) in my 928S ROW '81 with 5-speed manual.

I've started out with some of the tests in the WSM (27 p10-13) and got the following results:

Troubleshooting tempostat:
p10 - 1) Fuse: OK!
p10 - 2) Vacuum system: OK!
p10 - 3) Bending hoses: OK - None!
p10 - 4) Electric connection on vacuum servo: Not sure
p10 - 5) Microswitch behind clutch pedal: OK!

Checking vacuum servo:
p11 - 3) The vacuum servo should move the throttle: OK - It does!

Checking multiple pin plug, voltage:
p12 - 1) OK! - 12V between terminal 5 and 12.
p12 - 2) OK! - 12V between terminal 6 and 12 when braking.
p12 - 3) NOT OK!! - 12V between terminal 8 and 12 all the time.
p12 - 4) NOT OK!! - 0V between terminal 9 and 12 all the time.
p12 - 5) NOT OK!! - 0V between terminal 10 and 12 all the time.

Checking multiple pin plug, ohm:
p13 - 1) OK! Between terminal 12 and ground 0 ohm
p13 - 2) OK! Between terminal 3 and 7 = 14,3 ohm (almost =14 ohm)
p13 - 3) Didn't check - since I was alone when testing.

The Cruise CPU should be working - I just bought since I though that was the failing part.

I guess the problem is my "signal, wiper/wash, cruise switch" but the signal and wiper/wash works fine.

Any suggestions how to move further?

Thanks in advance

SharkSkin

See if the switch is plugged in. If it is, you probably need to replace it.