Dodge Ram Truck 1500-2500-3500. Manual — part 950

P0685-AUTO SHUTDOWN RELAY CONTROL CIRCUIT (CONTINUED)

For the Engine circuit diagram (Refer to 9 - ENGINE - SCHEMATICS AND DIAGRAMS).

For a complete wiring diagram Refer to Section 8W.

•

When Monitored:
With ignition on. Battery voltage above 10 volts.

•

Set Condition:
The actual ASD state is not equal to the desired ASD state. One Trip Fault. Three good trips to turn off the
MIL.

Possible Causes

INTERNAL FUSED B+ CIRCUITS

(K51) ASD RELAY CONTROL CIRCUIT OPEN

(K51) ASD RELAY CONTROL CIRCUIT SHORTED TO GROUND

ASD RELAY

PCM

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

Diagnostic Test

1.

ASD RELAY OPERATION

Ignition on, engine not running.

With a scan tool, actuate the ASD Relay.

Is the ASD Relay operating?

Yes

>> Refer to the INTERMITTENT CONDITION Diagnostic Procedure.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

No

>> Go To 2

2.

INTERNAL FUSED B+ CIRCUITS

Turn the ignition off.

Remove the ASD Relay from the IPM.

Using a 12-volt test light connected to ground, probe the Internal
Fused B+ circuits in the IPM.

Does the test light illuminate brightly?

Yes

>> Go To 3

No

>> Repair the open or short to ground in the Internal Fused

B+ circuits. Inspect and replace any open fuses.

Perform the POWERTRAIN VERIFICATION TEST. (Refer
to 9 - ENGINE - STANDARD PROCEDURE)

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ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

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P0685-AUTO SHUTDOWN RELAY CONTROL CIRCUIT (CONTINUED)

3.

ASD RELAY

Measure the resistance of the ASD Relay Coil.

Is the resistance between 60 to 80 ohms?

Yes

>> Go To 4

No

>> Replace the ASD Relay.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

4.

(K51) ASD RELAY CONTROL CIRCUIT OPEN

Disconnect the C3 PCM harness connector.

CAUTION: Do not probe the PCM harness connectors. Probing
the PCM harness connectors will damage the PCM terminals
resulting in poor terminal to pin connection. Install Miller Special
Tool #8815 to perform diagnosis.
Measure the resistance of the (K51) ASD Relay Control circuit from
the IPM to the appropriate terminals of special tool #8815.

Is the resistance below 5.0 ohms?

Yes

>> Go To 5

No

>> Repair the open in the (K51) ASD Relay Control circuit.

Perform the POWERTRAIN VERIFICATION TEST. (Refer
to 9 - ENGINE - STANDARD PROCEDURE)

5.

(K51) ASD RELAY CONTROL CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (K51) ASD Relay
Control circuit in the IPM.

Is the resistance below 100 ohms?

Yes

>> Repair the short to ground in the (K51) ASD Relay Control

circuit.

Perform the POWERTRAIN VERIFICATION TEST. (Refer
to 9 - ENGINE - STANDARD PROCEDURE)

No

>> Go To 6

DR/DH

ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

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P0685-AUTO SHUTDOWN RELAY CONTROL CIRCUIT (CONTINUED)

6.

PCM

NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal
push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and
Ground circuits.

Were there any problems found?

Yes

>> Repair as necessary.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

No

>> Replace and program the Powertrain Control Module per Service Information.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

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ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

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P0688-AUTO SHUTDOWN RELAY SENSE CIRCUIT LOW

DR/DH

ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

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