P0562

DTC P0562 System Voltage Low




Circuit Description
The Powertrain Control Module (PCM) monitors the system voltage on the ignition positive voltage terminals to the PCM. A system voltage DTC sets whenever the voltage is below a calibrated value.

Conditions for Running the DTC
The engine speed is more than 1300 RPM.

Conditions for Setting the DTC
The ignition voltage is less than 10 volts for 240 seconds.

Action Taken When the DTC Sets
- The PCM records the operating conditions at the time the diagnostic fails. The Failure Records buffers stores this information.
- A history DTC is stored.

Conditions for Clearing the DTC
- A history DTC clears after 40 consecutive warm up cycles without a fault.
- The scan tool can clear the DTC.

Diagnostic Aids
Whenever a DTC sets when an accessory is operated, check for a poor connection or an excessive current draw.

Step 1:

Steps 2 - 5:

Steps 6 - 9:

Test Description
The numbers below refers to the step numbers on the Diagnostic Table.
1. The Powertrain OBD System Check prompts you to complete some of the basic checks and to store the freeze frame and failure records data on the scan tool if applicable. This creates an electronic copy of the data captured when this DTC set. The scan tool stores this data for later reference.
2. This step checks if the generator is malfunctioning under load conditions.
3. The PCM Controlled Generator Diagnosis will further check the PCMs control of the generator.
4. This step checks the ignition positive voltage circuit #2 for any excessive resistance. An open circuit will cause a no start condition.
7. Program the replacement PCM and perform the crankshaft position system variation learn procedure. Refer to the latest Isuzu Technical Communications System (ITCS) procedures for PCM programming.
9. If no malfunctions are present at this point and no additional DTCs were set, refer to Diagnostic Aids for additional checks and information.