Cruise Control with Digital Dash

[Guest TwoDoorBuickMan]

Does anyone know where I can obtain information about Cruise Control specific to a digital dash? I recently purchased a 1986 Regal with a digital dash. Everything on the car works except the cruise control. I have checked out the usual suspects - servo - switch - connections. I suspect it has something to do with the speed sensor and do not want to tear into the dash until I know for sure, or know that replacements are available. Any help will be appreciated.

[joe_padavano]

The Chassis Service Manual should have all the info for troubleshooting. I have a 1986 Olds CSM that covers the Cutlass (equivalent to your Regal) and the cruise system and related troubleshooting info is well documented there, along with the wiring. The VSS on these cars is actually behind the dash, mounted to the speedo. The speedo is cable driven and there's an optical VSS that is activated by a light chopper wheel on the speedo.

I assume you've checked all the vacuum hoses and connections and have verified that the cruise actuator is functioning properly?

[Reatta Man]

The service module should have a trouble tree for tracing signals and the power supply.

Typical check points will include the fuse box, junctions in the wiring harness and connector points. Signal checks will likely include measuring voltage going into and out of a sensor or processor.

Good luck!

[Guest TwoDoorBuickMan]

Joe

Thanks for your response. I am guessing from what you said that the VSS is the same for a digital and non digital dash. I have a boxful of Cruise Control parts from non digital cars including several VSS units. I didn't want to take the dash apart until I felt I had a good shot at fixing it.

Thanks again!

Paul

[joe_padavano]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: TwoDoorBuickMan</div><div class="ubbcode-body">Joe

Thanks for your response. I am guessing from what you said that the VSS is the same for a digital and non digital dash. </div></div>

Unfortunately, I don't know. Olds didn't have a digital dash option in 86, so there is no discussion of it in my CSM. Your dash needs a VSS signal from someplace, and as far as I can tell, all the transmissions used in the RWD Buicks used a cable-drive speedo, so there needs to be a mechanical-to-electrical VSS someplace.