P0562-BATTERY VOLTAGE LOW





For a complete wiring diagram Refer to Section 8W.



Possible Causes
RESISTANCE IN THE (A801) BATTERY POSITIVE CIRCUIT
RESISTANCE IN THE GENERATOR CASE GROUND
(K125) GENERATOR FIELD CONTROL CIRCUIT OPEN
(K125) GENERATOR FIELD CONTROL CIRCUIT SHORTED TO GROUND
GENERATOR
PCM

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



Diagnostic Test

1. ACTIVE DTC

NOTE: Make sure the Battery is in good condition. Using the Midtronics Battery Tester, test the Battery before continuing.

NOTE: Inspect the vehicle for after market accessories that may exceed the Generator System output.

NOTE: Make sure the generator drive belt is in good operating condition.

NOTE: Inspect the fuses in the TIPM. If an open fuse is found, use the wire diagram/schematic as a guide, inspect the wiring and connectors for damage.


Start the engine.
Allow the engine to reach normal operating temperature.
With a scan tool, select View DTCs.

NOTE: It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.



Is the DTC Active or Pending at this time?

Yes


No

2. BATTERY

NOTE: Make sure the Battery is in good condition. Using the Midtronics Battery Tester or an equivalent Battery tester, test the Battery before continuing.



Does the Battery pass the load test for this specific application?

Yes


No

3. (A801) B+ CIRCUIT HIGH RESISTANCE


WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

NOTE: Make sure all wires are clear of the engine's moving parts.


Measure the voltage between the (A801) B+ Terminal at the Generator and the Battery + Post.
Start the engine.

Is the voltage above 0.4 of a volt?

Yes


No

4. GENERATOR CASE GROUND HIGH RESISTANCE

Ignition on, engine not running.
Start the engine.
Allow the engine to reach normal operating temperature.

NOTE: Make sure all wires are clear of the engine's moving parts.


Measure the voltage between the Generator case and Battery ground post.

Is the voltage above 0.1 of a volt?

Yes


No

5. GENERATOR OPERATION



Turn the ignition off.
Disconnect the Generator Field harness connector.
Using a 12-volt test light connected to ground, probe the (K125) Generator Field Control circuit in the Generator Field harness connector.

NOTE: Make sure the test light is probing the circuit before actuating the Relay or a DTC may set and not allow the actuation.


Ignition on, engine not running.
With the scan tool, actuate the Gen Field Control circuit.

Does the test light illuminate brightly and flash on and off?

Yes


No

6. (K125) GENERATOR FIELD CONTROL CIRCUIT OPEN



Turn the ignition off.
Disconnect the C2 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 (K125) Gen Field Control circuit from the Generator harness connector to the appropriate terminal of the special tool #8815.

Is the resistance below 5.0 ohms?

Yes


No

7. (K125) GENERATOR FIELD CONTROL CIRCUIT SHORTED TO GROUND



Measure the resistance between ground and the (K125) Gen Field Control circuit in the Generator Field harness connector.

Is the resistance below 100 ohms?

Yes


No

8. 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


No