TEST
ACTION
APPLICABILITY
2
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DTC When Monitored and Set Conditions. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?
All
Yes
→ Repair as necessary.
Perform ROAD TEST VERIFICATION - VER-2.
No
→ Test Complete.
3
Turn the ignition off.
Install a substitute relay in place of the High Speed Radiator Fan Relay.
Turn the ignition on.
With the DRB, actuate the High Speed Radiator Fan Relay.
Is the High Speed Radiator Fan Relay clicking?
All
Yes
→ Replace the High Speed Radiator Fan Relay.
Perform ROAD TEST VERIFICATION - VER-2.
No
→ Go To 4
4
Turn the ignition off.
Disconnect the ECM harness connectors.
Remove the High Speed Radiator Fan Relay from the PDC.
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.
Measure the voltage of the High Speed Radiator Fan Control circuit.
Is the voltage below 1.0 volt?
All
Yes
→ Go To 5
No
→ Repair the High Speed Radiator Fan Control circuit for a short to
voltage.
Perform ROAD TEST VERIFICATION - VER-2.
5
If there are no possible causes remaining, view repair.
All
Repair
Replace and program the Engine Control Module in accordance
with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
100
DRIVEABILITY - DIESEL
P0481-FAN 2 CONTROL CIRCUIT SHORT CIRCUIT —
Continued