Posted on October 27, 2020 C7 and C9 Industrial Engines Troubleshooting – Battery Problem Probable Causes Battery Switched Battery Circuit Recommended Actions Download the Product Status Report from the engine ECM before performing any troubleshooting or clearing diagnostic trouble codes. Troubleshoot any active codes before continuing with this procedure. Table 1 Troubleshooting Test Steps Values Results 1.Check the Battery A. Verify that the battery is no longer able to hold a charge. Refer to Systems Operation/Testing and Adjusting, “Battery – Test”. Battery Result: The battery is OK. Proceed to Test Step 2. Result: The battery is not OK. Repair: Replace the battery. Refer to Disassembly and Assembly for the correct procedure. 2. Check the Switched Battery Circuit A. Verify that a switched battery circuit drained the battery by being left in the ON position. Switched battery circuit Result: The switched battery circuit drained the battery by being left in the ON position. Repair: Charge the battery. Verify that the battery is able to maintain a charge. Refer to Systems Operation/Testing and Adjusting for the correct procedure.