Dodge Ram Truck 1500-2500-3500. Manual — part 1086
P0478-HIGH VOLTAGE ON THE ENGINE BRAKE DRIVER (CONTINUED)
3.
Engine Brake Driver Control Circuit
Turn the ignition off.
Remove the Engine Brake Driver Relay.
Disconnect the ECM harness connectors.
Check connectors - Clean/repair as necessary.
Measure the voltage of the Engine Brake Driver Control Circuit between the relay terminal and battery negative.
Is the voltage less than 1 volt?
Yes
>> Go To 4
No
>> Repair Engine Brake Driver Control Circuit shorted to voltage.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
4.
Engine brake relay
Measure the resistance between terminals 85 and 86 of the engine brake relay.
Is the resistance less than 10 ohms?
Yes
>> Replace the engine brake relay.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
No
>> Go To 5
5.
ECM
Reconnect the ECM harness connectors.
Reinstall the Engine Brake relay.
Ignition on, engine not running.
While monitoring with the scan tool, remove the Engine Brake Driver Relay.
Did P0477 set?
Yes
>> Refer to the INTERMITTENT CONDITION Symptom (Diagnostic Procedure). (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
No
>> Replace the ECM.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
9 - 1266
ENGINE - ELECTRICAL DIAGNOSTICS - DIESEL
DR/DH
P0480-FAN CLUTCH
DR/DH
ENGINE - ELECTRICAL DIAGNOSTICS - DIESEL
9 - 1267
P0480-FAN CLUTCH (CONTINUED)
For the Engine circuit diagram (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/ENGINE CON-
TROL MODULE - SCHEMATIC - ELECTRICAL)
For a complete wiring diagram Refer to Section 8W.
•
When Monitored:
When the ignition is on.
•
Set Condition:
The PWM signal to the fan clutch does not match the PWM signal from the fan clutch.
Possible Causes
FAN CLUTCH
WIRE HARNESS DAMAGED
OPEN FAN CLUTCH (K160) DRIVER CIRCUIT
(K160) DRIVER CIRCUIT SHORTED TO (K690) RETURN CIRCUIT
(K160) DRIVER CIRCUIT SHORTED TO BATTERY NEGATIVE
INTERMITTENT CONDITION
ECM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.
FAN CLUTCH
Disconnect the fan clutch harness connector.
Check connectors - Clean/repair as necessary.
Measure the resistance between the fan clutch (K160) driver circuit
and the fan speed (K690) sensor return circuit on the fan clutch
assembly.
Is the resistance less than 10 Ohms?
Yes
>> Replace the fan clutch.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
No
>> Go To 2
9 - 1268
ENGINE - ELECTRICAL DIAGNOSTICS - DIESEL
DR/DH
P0480-FAN CLUTCH (CONTINUED)
2.
FAN CLUTCH
Disconnect the Fan Clutch harness connectors.
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance between the fan clutch (K160) driver circuit
and the fan clutch (F504) battery supply circuit on the fan clutch
assembly.
Is the resistance less than 6 Ohms or greater than 10 Ohms?
Yes
>> Replace the fan clutch.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
No
>> Go To 3
3.
OPEN FAN CLUTCH (K160) DRIVER CIRCUIT
Disconnect the ECM harness connectors.
Check connectors - Clean/repair as necessary.
Measure the resistance of the fan clutch (K160) driver circuit between
the ECM harness connector and the fan clutch harness connector.
Is the resistance less than 10 Ohms?
Yes
>> Go To 4
No
>> Repair the open fan clutch (K160) river circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
DR/DH
ENGINE - ELECTRICAL DIAGNOSTICS - DIESEL
9 - 1269
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст