U1132-GENERATOR COMMUNICATION

For a complete wiring diagram Refer to Section 8W

When Monitored:
Continuously while the system is active.
Set Condition:
The ECM isn't receiving a LIN bus message from the Generator.

Possible Causes

INTERMITTENT DTC

(D509) LIN BUS CIRCUIT OPEN OR HIGH RESISTANCE

GENERATOR

ENGINE CONTROL MODULE (ECM)

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

Diagnostic Test

1. DTC IS ACTIVE

Turn the ignition on.
With a scan tool, View DTCs.
Record all DTC information.

NOTE: If DTC U1008 LIN 1 BUS is active in addition to this DTC, perform the diagnostic procedure for that DTC before continuing with this test.

With a scan tool, Clear DTCs.
Start the engine and allow it to reach normal operating temperature.
Monitor the scan tool for at least 2 minutes.
With a scan tool, View DTCs.

Is the status Active for this DTC?

Yes

Go To 2

No

Refer to the INTERMITTENT CONDITION Diagnostic Procedure. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

2. (D509) LIN BUS CIRCUIT OPEN OR HIGH RESISTANCE

Turn the ignition off.
Disconnect the Generator harness connector.
Disconnect the Engine Control Module (ECM) harness connector.
Measure the resistance of the (D509) LIN Bus circuit between the Generator harness connector and the Engine Control Module (ECM) harness connector.

Is the resistance below 10.0 ohms for both measurements?

Yes

Go To 3

No

Repair the (D509) LIN Bus circuit for an open circuit or high resistance.
Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

3. GENERATOR

Ignition off, engine not running.
Connect the Engine Control Module (ECM) harness connector.
Replace the Generator in accordance with the Service Information.
Turn the ignition on.
With a scan tool, Clear DTCs.
Start the engine and allow it to reach normal operating temperature.
Monitor the scan tool for at least 2 minutes.
With a scan tool, View DTCs.

Is the status Active for this DTC?

Yes

Go to 4

No

Test Complete.
Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

4. ENGINE CONTROL MODULE (ECM)

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Glow Plug Module and the Engine Control Module (ECM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
Look for the data to change or for the DTC to reset during the wiggle test.
Refer to any Technical Service Bulletins that may apply.

Were any problems found?

Yes

Repair as necessary.

Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

No

Replace the Engine Control Module (ECM) in accordance with the Service Information.
Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - STANDARD PROCEDURE)