1994 SSE, turn signal lever/switch and wires to the main wire harness replaced, vacuum diaphram unit ok, no blown fuses, DIC and speedometer OK, but cruise control still does not work.

I would like the location of the control module (little black box that converts the signal to the diaphram).

Thanks

From my 94 GM service manual " The pcm controls vehicle speed during cruise control operation. The PCM receives input signals from the cruise control switches (on the multifunction lever), the Throttle position sensor, the vehicle speed sensor, and both brake switches. The PCM processes these inputs together with engine control information to control the servlo'* vacum & vent solenoid valves." Since you have replaced the switches in the multifuntion lever and checked fuses etc, I would look closely at the brake switches. You might want to test them both to make sure the contacts are opening and closing properly when brake pedal it pushed. There is no other cruise control module.

Flatlander

Cruise Control Module part # 25110889 Fits Many Buicks, Chevys,Olds,Pontiacs from 1988-1994

Is this the PCM you are refering to? If it is this is the part I am trying locate (physical location) on the vehicle.

My brake lights work properly. When you say to check the contacts, is that a second brake switch somewhere?

The actual cruise control is located on top of the transmission. You will be able to follow a throttle cable from the throttle body down to it. Frequently if the cruise is not working up to par the vacuum line on it is deteriorating.

Thanks, vacuum lines look OK, How about that brake switch. how do I check that?

The brake switch assembly is mounted under the dash and the brake pedal lever activates it. It also has a vacum line running to it from the cruise control servo. When you press the brake the vacum is vented and allows the cruise control servo to quickly let the throttle return. This hose goes from the brake switch to the vacum servo under the hood. If the hose is disconnected, cracked or broken you will have problems with the cruise not engaging.

Flatlander

Excellent! The car is in the transmission shop so will be a few days till I can check everything. Will let you know.