2006 DODGE RAM SRT-10 battery

P0478-HIGH VOLTAGE ON THE ENGINE BRAKE DRIVER
For a complete wiring diagramRefer to Section 8W.
When Monitored:
When the ignition is on.
Set Condition:
When the signal from the engine brake driver output does not match the signal from the engine brake driver
feedback.
Possible Causes
RELAY LOOSE
ENGINE BRAKE DRIVER CONTROL CIRCUIT SHORTED TO VOLTAGE
ENGINE BRAKE RELAY
INTERMITTENT CONDITION
ECM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.RELAY
Ignition on, engine not running.
With the scan tool, actuate the Engine Brake Driver Relay.
Can you hear the Relay clicking?
Ye s>>
Go To 2
No>>
Go To 3
2.RELAY LOOSE
While the relay is clicking, wiggle the wiring harness and connectors.
Does this interrupt the clicking?
Ye s>>
Repair the loose connection.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
No>>
Go To 3
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 therelay terminal and battery negative.
Is the voltage less than 1 volt?
Ye s>>
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)

For a complete wiring diagramRefer to Section 8W.
When Monitored:
When the ignition is on.
Set Condition:
When the control coil is electrically shorted or open.
Possible Causes
FA N C L U TC H
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.FA N C L U T C H
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?
Ye s>>
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

2.FA N C L U T C H
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.
Istheresistancelessthan6Ohmsorgreaterthan10Ohms?
Ye s>>
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?
Ye s>>
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)

4.(K160) DRIVER CIRCUIT SHORTED TO (K690) RETURN CIRCUIT
Measure the resistance between the fan clutch (K160) driver circuit and
the fan speed sensor (K690) return circuit at the sensor harness con-
nector.
Is the resistance greater than 100K Ohms?
Ye s>>
Go To 5
No>>
Repair the (K160) Driver circuit shorted to (K690) Return
circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
5.(K160) DRIVER CIRCUIT SHORTED TO BATTERY NEGATIVE
Measure the resistance between the fan clutch (K160) driver circuit and
the battery negative.
Is the resistance greater than 100k Ohms?
Ye s>>
Go To 6
No>>
Repair the (K160) Driver circuit shorted to battery negative.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)

6.ECM
Reconnect the ECM harness connectors.
Measure the resistance of the fan clutch (K160) driver circuit between
the fan clutch connector and battery negative.
Is the resistance greater than 100k Ohms?
Ye s>>
Refer to the INTERMITTENT CONDITION Symptom (Diag-
nostic Procedure). (Refer to 9 - ENGINE - DIAGNOSIS
AND TESTING)
No>>
replace the ECM.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)

3.FAN CLUTCH ASSEMBLEY SHORTED TO GROUND
Measure the resistance between the signal circuit in the fan clutch assembly and battery negative.
Is the resistance less than 10 Ohms?
Ye s>>
Replace the fan clutch assembly.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
No>>
Go To 4
4.(K161) SIGNAL CIRCUIT SHORT TO (K668) 5-VOLT SUPPLY CIRCUIT
Disconnect the Fan clutch connector.
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance between the (K161) signal circuit in the fan
clutch assembly and the battery (K668) 5-volt supply circuit in the fan
clutch assembly.
Is the resistance less than 10 Ohms?
Ye s>>
Replace the Fan clutch assembly.
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 5

7.(K161) SIGNAL CIRCUIT SHORTED TO RETURN IN THE HARNESS
Measure the resistance between the (K161) signal circuit in the fan
clutch assembly harness connector and the return circuit in the fan
clutch assembly harness connector.
Is the resistance less than 10 Ohms?
Ye s>>
Repair the shorted (K161) circuit.
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 8
8.(K161) SIGNAL CIRCUIT SHORTED TO VOLTAGE
Measure the voltage between the (K161) signal circuit in the fan clutch
assembly harness connector and battery negative.
Is the voltage greater than 1 volt?
Ye s>>
Repair the (K161) signal circuit shorted to voltage.
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 9

9.(K161) SIGNAL CIRCUIT IN ECM SHORTED TO GROUND INSIDE ECM
Reconnect the ECM harness connectors.
Measure the resistance between the (K161) signal circuit in the fan
clutch assembly harness connector and battery negative.
Is the resistance less than 10 Ohms?
Ye s>>
Replace the ECM.
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 10
10.(K161) SIGNAL CIRCUIT SHORTED TO VOLTAGE IN THE ECM
Reconnect the fan harness connector.
Turn the ignition on.
While back probing the fan connector measure the voltage between the
fan speed (K161) signal circuit in the fan clutch assembly harness con-
nector and battery negative while manually rotating the fan blade.
Did voltage go from less than 0.7 volts to 4.5 to 5.5 volts?
Ye s>>
Repair the Fan Speed (K161) Signal circuit in the engine
harness.
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 11