Originally Posted by Johnny Cetane

The code is low voltage to the ECM. Here's some info: WHEN MONITORED Continuous - key on or key off. SET CONDITION Loss of voltage detected at the ECM for a calibrated amount of time. POSSIBLE CAUSES * Poor connections at the batteries * Low battery voltage * Open fused B+ to ECM * Open ground circuit * Battery + shorted to other circuits * Return circuit shorted * Battery + shorted to ground * Intermittent condition Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. DIAGNOSTIC TEST 1. POOR CONNECTIONS AT THE BATTERIES Visually inspect the wiring at the battery for damaged wires, or corrosion. Q: Are the connections tight and free of corrosion? YES: Go To 2 NO: Repair the poor connections at the batteries. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). See: Verification Tests\Powertrain Verification Test Ver - 1 2. LOW BATTERY VOLTAGE Measure the voltage between the positive and negative posts of the batteries. Q: Is the battery voltages both above 12 volts? YES: Go To 3 NO: Recharge or replace the battery (s). Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). See: Verification Tests\Powertrain Verification Test Ver - 1 3. OPEN FUSED B+ TO ECM Turn the ignition off. Disconnect the ECM harness connectors. Turn the ignition on. Measure the resistance between the positive battery post and the ECM supply circuits. Q: Is the resistance less than 10 Ohms? YES: Go To 4 NO: Repair the open fused B+ circuit to ECM. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). See: Verification Tests\Powertrain Verification Test Ver - 1 4. OPEN GROUND CIRCUIT Measure the resistance between the negative battery post and the ECM ground circuits. Q: Is the resistance less than 10 Ohms? YES: Go To 5 NO: Repair the open ground circuit. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). See: Verification Tests\Powertrain Verification Test Ver - 1 5. BATTERY + SHORTED TO OTHER CIRCUITS Measure the resistance between the ECM supply circuits and all other circuits in the ECM harness connector, except other supply circuits. Q: Is the resistance greater than 100k Ohms? YES: Go To 6 NO: Repair the battery circuit short to other circuits in engine harness. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). See: Verification Tests\Powertrain Verification Test Ver - 1 6. RETURN CIRCUIT SHORTED Measure the resistance between the ECM return circuits and all other circuits in the ECM harness connector, except other return circuits. Q: Is the resistance greater than 100k Ohms? YES: Go To 7 NO: Repair or replace the engine harness. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). See: Verification Tests\Powertrain Verification Test Ver - 1 7. BATTERY + SHORTED TO GROUND Measure the resistance between the ECM B+ supply circuits and ground. Q: Is the resistance greater than 100k Ohms? YES: Refer to the INTERMITTENT CONDITION Symptom (Diagnostic Procedure). See: Initial Inspection and Diagnostic Overview\Diagnostic Strategies NO: Repair Battery + shorted to ground. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). See: Verification Tests\Powertrain Verification Test Ver - 1