Mitsubishi 1989-1993 GALANT Service Manual page 494

AUTO-CRUISE CONTROL SYSTEM - Troubleshooting
Trouble symptom
The set vehicle speed varies
l
greatly upward or downward.
"Hunching" (repeated alternating
l
acceleration and deceleration) oc-
curs after setting is made.
The auto-cruise control system is not
depressed.
ransaxle)
It is canceled, however, when the
noved to the "N" position. (vehicles
vith an automatic transaxle)
Probable cause
Malfunction of the ve-
Malfunction of the spee-
dometer cable or spee-
dometer drive gear
Auto-cruise vacuum
pump circuit poor con-
tact
Malfunction of the auto-
cruise vacuum pump
Malfunction of the ECU
Damaged or discon-
light switch input circuit;
brake switch (for auto-
cruise control) malfunc-
tion (short-circuit)
Auto-cruise vacuum
pump drive circuit short-
circuit.
Malfunction of the ECU
Damaged or discon-
pedal position switch
input circuit
Clutch pedal position
switch improper installa-
tion (won't switch ON)
Malfunction of the ECU
Damaged or discon-
neutral position switch
input circuit
Improper adjustment of
park/neutral position
switch
Malfunction of the ECU
Temporary damaged or
disconnected wiring of
SET switch input circuit
Auto-cruise vacuum
pump circuit poor con-
tact
Malfunction of the auto-
cruise vacuum pump
and actuator (including
clogging of negative
pressure passage)
Malfunction of the ECU
TSB Revision
Check chart No. Remedy
Repair the vehicle spee
sensor system, or re-
place the part.
Repair the auto-cruise
vacuum pump or replac
the part.
Replace the ECU.
If the input check code Repair the harness or re
place the stop light
switch.
function. No.6
Repair the harness or re
place the auto-cruise va
Replace the ECU.
If the input check code Repair the harness, or
repair or replace the
function. No.8 clutch pedal position
switch.
Replace the ECU.
If the input check code Repair the harness, or
repair or replace the
function. No.7 park/neutral position
switch.
Replace the ECU.
Repair the harness or re-
place the SET switch.
Repair the harness or re-
place the auto-cruise va-
cuum pump and actua-
tor.
Replace the ECU.
I