Dodge Ram Truck 1500-2500-3500. Manual — part 1087

P0480-FAN CLUTCH (CONTINUED)

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
connector.

Is the resistance greater than 100K Ohms?

Yes

>> 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?

Yes

>> Go To 6

No

>> Repair the (K160) Driver circuit shorted to battery nega-

tive.

Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)

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ENGINE - ELECTRICAL DIAGNOSTICS - DIESEL

DR/DH

P0480-FAN CLUTCH (CONTINUED)

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?

Yes

>> Refer to the INTERMITTENT CONDITION Symptom

(Diagnostic Procedure). (Refer to 9 - ENGINE - DIAGNO-
SIS 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)

DR/DH

ENGINE - ELECTRICAL DIAGNOSTICS - DIESEL

9 - 1271

P0483-FAN SPEED

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ENGINE - ELECTRICAL DIAGNOSTICS - DIESEL

DR/DH

P0483-FAN SPEED (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:
While the engine is running.

•

Set Condition:
The actual fan speed is less than 75 RPM or more than 4000 RPM.

Possible Causes

OTHER DTC’S

(K161) SIGNAL CIRCUIT SHORT TO (K668) 5-VOLT SUPPLY CIRCUIT

(K161) SIGNAL CIRCUIT OPEN FROM ECM TO FAN CLUTCH ASSEMBLY

(K668) 5-VOLT SUPPLY CKT OPEN FROM ECM HARNESS CONNECTOR TO FAN CLUTCH HARNESS
CONNECTOR

INTERMITTENT CONDITION

(K161) SIGNAL CIRCUIT SHORTED TO (690) RETURN IN THE HARNESS

(K161) SIGNAL CIRCUIT SHORTED TO VOLTAGE

(K161) SIGNAL CIRCUIT IN ECM SHORTED TO GROUND INSIDE ECM

(K161) SIGNAL CIRCUIT SHORTED TO VOLTAGE IN THE ECM

(K668) 5-VOLT SUPPLY CIRCUIT IN ECM

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)

Diagnostic Test

1.

OTHER DTC’S PRESENT

With the scan tool, read DTCs.

Is DTC P0480 present?

Yes

>> Repair other DTC’s first.

Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)

No

>> Go To 2

2.

FAN CLUTCH SHORTED

Disconnect the wiring harness from the fan clutch assembly.

NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance between the signal circuit in the fan clutch assembly and the return circuit in the fan clutch
assembly.

Is the resistance less than 10 Ohms?

Yes

>> 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 3

DR/DH

ENGINE - ELECTRICAL DIAGNOSTICS - DIESEL

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