Working cruise control
03-05-2006, 05:18 PM
#16
Rennlist Member
Originally Posted by corporatezombie
Cruise control diagnostics:
I'm trying to diagnose the trouble with my cruise control. ('87 S4 Auto UK)
At first I thought it was too much play in the bowden cable - tightened so there is about 1-2mm of slack - no effect.
So then I thought - ahh it's probably vacuum - so I'm waiting for my new Mityvac to arrive on Tuesday.
But - I thought - I might as well have a go at the electrical diagnosis in the meantime and
The results are WIERD!
With the ignition on and engine not running.
between terminals 5 and 12 I'm getting about 8.5 volts instead of battery voltage.
Between terminals 6 and 12 that is supposed to be 0 volts until the brake is pressed is showing around 8.5 volts all the time.
Terminals 8,9,10 don't seem to be getting the switch inputs from the cruise control lever.
I have checked the lever and the switch is working.
Any ideas anyone?
Bruce
'87 S4 Auto UK - Lagoon Green
I'm trying to diagnose the trouble with my cruise control. ('87 S4 Auto UK)
At first I thought it was too much play in the bowden cable - tightened so there is about 1-2mm of slack - no effect.
So then I thought - ahh it's probably vacuum - so I'm waiting for my new Mityvac to arrive on Tuesday.
But - I thought - I might as well have a go at the electrical diagnosis in the meantime and
The results are WIERD!
With the ignition on and engine not running.
between terminals 5 and 12 I'm getting about 8.5 volts instead of battery voltage.
Between terminals 6 and 12 that is supposed to be 0 volts until the brake is pressed is showing around 8.5 volts all the time.
Terminals 8,9,10 don't seem to be getting the switch inputs from the cruise control lever.
I have checked the lever and the switch is working.
Any ideas anyone?
Bruce
'87 S4 Auto UK - Lagoon Green
