Cruise Control - Troubleshooting Hints
Number 84-9-11 Date 7/84Subject: TROUBLESHOOTING HINTS- 1984 CRUISE CONTROL (K34)
CONDITION CAUSE CORRECTION
Inoperative System No power to module terminals Check fuse, brake and clutch
"G" and "A". switches, turn signal handle,
pinched wires in steering column.
Open "ground" at module Repair ground circuit, (run new
terminal "J", servo terminal ground if necessary).
"C", or VSS ground.
Open SPS circuit (module-servo Repair leads and/or replace servo.
leads F-B, H-D or SPS coil in
servo).
Vac release valve circuit Adjust or replace vacuum release
open to atmosphere. valve, check hoses, or repair circuit.
No high and low voltage Check for open leads or bad buffer
signal at module speed amplifier or speedometer. Check
sender terminal "D". ground and B+ input.
No 12 volt signal at module Check for open lead or connector
"set/coast" terminal "L". or bad turn signal handle. Check for
terminal in proper cavity.
No vacuum at small hose to Check for plugged, pinched, dis-
servo. connected vac hoses, incorrectly
positioned 3-way check valve, restricted engine vacuum fitting.
Checked servo position rod Replace servo.
and spring.
Leaky servo and/or inoperative Replace servo.
valves.
Disconnect servo linkage. Reconnect.
Inoperative module. Replace module.
CONDITION CAUSE CORRECTION
Vehicle Surges Excess slack in servo linkage. Adjust.
Dry speedometer cable. Lubricate.
Spikes on B+ lines. Find cause and repair.
Turn signal or other Reposition electrical leads away
electrical device interfer- from cruise or VSS buffer leads.
ference. Check for poor ground at module,
servo, or VSS buffer.
Restricted (kinked or leaking) Inspect hoses and reposition
vacuum supply hose to as required.
accumulator or servo.
Crossed vac and vent electrical Rewire.
leads between module and servo.
Binding servo Bowdin cable. Replace.
Torque converter clutch Normal (not a cruise problem).
cutting in and out.
Intermittent ground. Check for poor ground at servo, module,
VSS buffer. (Generally this is a common
ground at the I.P. or servo.)
Servo valves sticking. Replace servo.
Inoperative module. Replace module.
Cruise Set Speed Excess slack in servo linkage. Adjust.
High or Low
Incorrect module part number Make correction.
usage.
Inoperative module. Replace.
No Resume Function Incorrect operator technique. Advise operator.
(If R/A held down for more than 1 second, system reverts to accel mode. Speed at time of release is new cruise speed.)
CONDITION CAUSE CORRECTION
Open connection at terminal Repair.
"A" of module or terminal in wrong cavity.
No "Tap Down" Function Incorrect operator technique Advise operator.
(Tap down held down in excess of .4 second.)
Incorrect module usage. Make correction.
Vehicle Cruises or Crossed vac and vent wires. Rewire.
Resumes Beyond
Set Speed Inoperative turn signal mode Replace.
control switch.
Sticking valves in servo. Replace servo.
Binding throttle linkage. Make correction.
Inoperative module. Replace module.
Incorrect module usage. Make correction.
Inoperative speed sensor buffer. Replace buffer.
Cruise Drops Out While Inoperative module. Replace module.
Tapping Down