DaimlerChrysler Jeep Grand Cherokee 2002, Service Manual

Page: 125 / 284

Symptom:
P0560-SYSTEM VOLTAGE TOO HIGH
When Monitored and Set Condition:
P0560-SYSTEM VOLTAGE TOO HIGH
When Monitored: With the engine running.
Set Condition: The ECM detects battery voltage is above 15.5 volts.
POSSIBLE CAUSES
GROUND CIRCUIT HIGH RESISTANCE
BATTERY SUPPLY OR ASD RELAY OUTPUT CIRCUIT HIGH RESISTANCE
GENERATOR FIELD CONTROL CIRCUIT SHORTED TO GROUND
GENERATOR INTERNALLY SHORTED TO GROUND
ENGINE CONTROL MODULE
TEST ACTION APPLICABILITY
1 NOTE: If DTC P1511 or P1512 is present with this DTC, diagnose DTCs P1511
and P1512 before diagnosing this DTC.
NOTE: The battery must be fully charged and the generator belt must be in
good condition and tensioned properly before continuing.
Turn the ignition off.
Disconnect the ECM harness connectors.
Using a 12-volt test light connected to 12-volts, check all of the ECM Ground circuits
including the Battery(-) Sense circuit.
Does the test light illuminate brightly for each circuit? All
Yes
→
Go To 2
No
→
Repair the Ground circuit(s) for high resistance.
Perform CHARGING VERIFICATION - VER-3.
2 Turn the ignition off.
Disconnect the ECM harness connectors.
Remove the ASD Relay from the PDC.
Connect a jumper wire between cavity 30 and cavity 87 of the ASD Relay connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, check all of the ECM Battery Supply
and ASD Relay Output circuits including the B) Sense circuit.
Does the test light illuminate brightly for each circuit? All
Yes
→
Go To 3
No
→
Repair the Battery Supply or ASD Relay Output circuit(s) for high
resistance.
Perform CHARGING VERIFICATION - VER-3.
117
DRIVEABILITY - DIESEL
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