TEST
ACTION
APPLICABILITY
3
Turn the ignition off.
Install a substitute relay in place of the ECM/PCM Relay.
Perform several ignition key cycles, pausing for at least 10 seconds between each
cycle.
Turn the ignition on.
With the DRB, read ECM DTCs.
Did this DTC set again?
All
Yes
→ Go To 4
No
→ Replace the ECM/PCM Relay.
Perform ROAD TEST VERIFICATION - VER-2.
4
Turn the ignition off.
Remove the ECM/PCM Relay from the IPM.
Disconnect the ECM harness connectors.
Measure the resistance of the ECM/PCM Relay Control circuit while wiggling the
wiring harness and connectors between the ECM and the IPM.
Was the resistance above 5.0 ohms at any time while wiggling the wiring harness and
connectors?
All
Yes
→ Repair the ECM/PCM Relay Control circuit for an intermittent
open.
Perform ROAD TEST VERIFICATION - VER-2.
No
→ Replace and program the Engine Control Module in accordance
with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
5
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.
159
DRIVEABILITY - DIESEL
P0685-ECM/PCM RELAY CONTROL CIRCUIT SHUTS OFF TOO EARLY —
Continued