Cruise Control - Revised Quick Check Diagnostic Routine
86chevy7Number: 86-157
Section: 9
Date: Sept., 1986
Subject: MODIFICATION OF DIAGNOSTTC ROUTINE ON THE CLARK BROS., KENT-MOORE, AND SPECMO CRUISE CONTROL "QUICK CHECKERS"
Model and Year: ALL VEHICLES WITH CRUISE CONTROL
TO: ALL CHEVROLET DEALERS
The existing diagnostic test procedure listed on the reverse side of these "Quick Checkers" includes five troubleshooting steps. Each step provides a reliable indication, by the illumination of a light, of the electrical continuity of specific components in the cruise control system. A large number of GM Dealership service personnel are under the misunderstanding that these same five steps, also, verify the condition of the cruise vacuum system. This is not the case. To clear up this mistaken assumption, an essential addition has been incorporated in the existing test procedure.
A sixth step (refer to example) has been added. This step allows the technician to check the cruise system vacuum integrity from the accumulator tank through the vacuum servo.
To obtain the new diagnostic stickers, contact your zone office or divisional service contact representative. Place the sticker over the one presently on the "Quick Checker." If additional stickers are needed in the future, contact:
SPECMO ENTERPRISES 2344 N. Woodward Avenue Royal Oak, MI 48073 (313) 399-5645
TEST AND CONDITION CORRECT RESPONSE OF LIGHTS
Ignition and Cruise Slider Switch On Off
1 ign. ON, slider switch OFF ALL
2 ign. ON, slider switch ON ON/OFF, Lamp * BRK R/A S/C
Vent, VAC, SPS Short
3 ign. ON, slider switch ON. ON/OFF, Lamp * BRK R/A VAC
push in S/C position ** Vent, SPS, S/C Short
4 ign. ON, slider switch ON. ON/OFF, Lamp * BRK Vent S/C
push in R/A position ** R/A, SPS, VAC Short
5 Roll vehicles 5-10 MPH VSS flashing, do not check any
ign. ON, slider switch ON *** other lights
6 Vacuum accumulator charged. ON/OFF lamp * S/C R/A
engine off. ign. ON. depress BRK, SPS Vent, VAC
S/C and R/A together ** Short
Servo goes full stroke and holds
* when equipped with cruise lamp ** if engine is running, throttle may go to full open position *** see special instructions for Pontiac P-car Fiero