1993 Cruise control vacuum line

[Robert252]

Originally Posted by ChevyTech

RE: Robert252

Here are two good cruise control threads:
http://67-72chevytrucks.com/vboard/s...d.php?t=532924

http://67-72chevytrucks.com/vboard/s...d.php?t=539665

I am busy and don't know when I will get back here to the board, but I work you through this, time permitting.

Here is some 1993 Cruise control information:

Testing at the cruise unit under the hood;

Unplug the wire connector from the cruise module on the cruise unit under the hood.
Check for power on the Pink wire with black stripe (with the key on) – there should be power.
Check for power on the Gray wire (with the key on and cruise switch on) – there should be power.
Check for power on the Brown wire (not touching the brake pedal) – there should be power.
Check for power on the Brown wire (while the brake pedal is pushed) – there should be NO power.

Give me the results of these tests.

Power flow:
Gages fuse - To Cruise module & cruise switch – Pink wire with black stripe
Cruise switch – to brake switch – gray wire
(Auto transmission vehicles) Brake switch to cruise module – Brown wire
(Manual transmission vehicles) Brake switch to clutch switch on gray wire with black stripe, through the clutch switch and to the cruise module in brown wire.

Cruise switch wires colors:
Pink wire with black stripe = power in from gage fuse
Gray wire = power out of switch to brake switch and cruise module
Dark blue wire = Set & coast
Dark green wire = Resume & accelerate

Cruise module wire colors:
Pink wire with black stripe = power in from gauge fuse
Black with white stripe = Ground
Brown wire = power back from brake switch (and clutch on manual transmission vehicles)
Dark blue wire = Set & coast - signal from cruise switch
Dark green wire = Resume & accelerate - signal from cruise switch
Gray wire = power from cruise switch
White wire = to PCM – (TCM on diesel engines)
Red with white stripe = Vehicle speed signal from DRAC module

Ok I checked for voltage on the pink = Have PWR
Checked for voltage on the grey wire = have PWR
Checked for voltage on the brown wire with brake not pushed = NO POWER.

But I do have a brake warning light that comes on when I get up to 35 mph. but it is not as bright as when I have the park brake on.