Symptom:
P0579-S/C SWITCH SIGNAL CIRCUIT SIGNAL VOLTAGE TOO LOW
POSSIBLE CAUSES
INTERMITTENT CONDITION
S/C ON/OFF/SET SWITCH
S/C RESUME/ACCEL SWITCH
S/C/ SWITCH SIGNAL CIRCUIT SHORTED TO SENSOR GROUND
S/C SWITCH SIGNAL CIRCUIT SHORTED TO GROUND
ECM
TEST
ACTION
APPLICABILITY
1
Turn the ignition on.
With the DRBIII
t
, read the S/C Switch voltage.
Is the S/C Switch voltage below 0.4 volt?
All
Yes
→
No
→
2
Turn the ignition on.
With the DRBIII
t
, monitor the S/C Switch voltage.
Disconnect the S/C ON/OFF/SET Switch harness connector.
Did the DRB reading change to above 4.7 volts?
All
Yes
→
Replace the S/C ON/OFF/SET Switch.
Perform SPEED CONTROL VERIFICATION - VER-4.
No
→
3
Turn the ignition on.
With the DRBIII
t
, monitor the S/C Switch voltage.
Disconnect the S/C Resume/Accel Switch harness connector.
Did the volt change to above 4.7 volts?
All
Yes
→
Replace the S/C Resume/Accel Switch.
Perform SPEED CONTROL VERIFICATION - VER-4.
No
→
4
Turn the ignition off.
Disconnect the S/C ON/OFF/SET Switch harness connector.
Disconnect the S/C RESUME/ACCEL Switch harness connector.
Disconnect the ECM harness connectors.
Measure the resistance between the S/C Switch Signal circuit and the Sensor Ground
circuit in the ECM harness connector.
Is the resistance below 5.0 ohms?
All
Yes
→
Repair the S/C Switch Signal circuit shorted to the Sensor Ground
circuit.
Perform SPEED CONTROL VERIFICATION - VER-4.
No
→
127
DRIVEABILITY - DIESEL
Summary of Contents for Jeep Grand Cherokee 2002
Page 8: ...NOTES viii ProCarManuals com...
Page 18: ...NOTES 10 ProCarManuals com...
Page 19: ...7 0 DIAGNOSTIC INFORMATION AND PROCEDURES 11 ProCarManuals com...
Page 262: ...NOTES 254 ProCarManuals com...
Page 265: ...C O M P O N E N T L O C A T I O N S 257 COMPONENT LOCATIONS ProCarManuals com...
Page 275: ...C O N N E C T O R P I N O U T S 267 CONNECTOR PINOUTS ProCarManuals com...
Page 280: ...NOTES 272 ProCarManuals com...
Page 282: ...NOTES 274 ProCarManuals com...
Page 283: ...11 0 CHARTS AND GRAPHS C H A R T S A N D G R A P H S 275 CHARTS AND GRAPHS ProCarManuals com...
Page 284: ...NOTES 276 ProCarManuals com...