Cruise Control - Updated Wiring & Circuit Description

9217buick04

Bulletin:
92-8-15

Date:
Jan. '92

Ref. No.:
92-123-8

Corp. Ref. No.:
118123R


SUBJECT:
SERVICE MANUAL UPDATE - SECTION 8A - CRUISE MODULE MECHANIZATION, NORMAL BRAKE SWITCH STATE

MODELS AFFECTED:
1992 ROADMASTER


1992 Roadmaster Sedans starting with VIN NR421429 and 1992 Roadmaster Estate Wagons were built with a cruise module that has to have the brake signal input pulled low at terminal "G" for cruise control to function. This is accomplished by a small amount of current flowing from the cruise module, through circuit 820, to the Center High Mount Stop Lamp (CHMSL) bulb to ground. When the brakes are applied and the brake switch closes, the cruise module and circuit 820 receive BATT voltage. This allows the CHMSL bulb to illuminate and the cruise module to sense that the brakes are applied.








Please replace pages 8A-34-0 and 8A-34-1 of the 1992 Service Manual with the revised page.

The brake switch mechanization, as shown on page 8A-34-0, has been re-drawn to show it in the "normally open" state. Step 2 of the troubleshooting hints, on page 8A-34-1, includes checking the CHMSL in the event cruise control is disabled.

For 1992 Roadmaster Sedans built before VIN NR421429, use the 1992 Preliminary Roadmaster Service Manual for Electrical Diagnosis and Repair.