Circuit/System Testing

Perform the Battery Inspection/Test .
NOTE: To accurately diagnose the charging system, the C1 Battery must be fully charged and capable of passing the Battery Inspection/Test.
Vehicle OFF. Disconnect the C1 Battery. Refer to Battery Negative Cable Disconnection and Connection .
Disconnect the B+ X4 cable connector at the K1 14V Power Module.
NOTE: The X4 harness connector at the 14V power module is connected to the positive terminal of the 12V battery through a 200 A fuse. When disconnected, the harness connector must be isolated from ground or any other conductor to prevent electrical spark when the 12V battery ground is reconnected.
Connect a test lamp between the C1 Battery positive terminal and the X4 terminal at the K1 14V Power Module.
Reconnect the C1 Battery. Refer to Battery Negative Cable Disconnection and Connection . Vehicle ON.
Measure and record the voltage between the X4 terminal at the K1 14V Power Module and ground.
Verify the scan tool Hybrid Powertrain Control Module Low-Voltage Circuit Voltage parameter in the 14V Power Module data list is within 0.5V of the voltage recorded in the previous step.
- If the voltage is not within the specified range
  Replace the K1 14V Power Module.
- If the voltage is within the specified range
Vehicle OFF, remove the test lamp.
Test for less than 2 Ω in the B+ circuit between the X4 cable connector and the C1 Battery positive terminal.
- If 2 Ω or greater
  Repair the open/high resistance in the circuit.
- If less than 2 Ω
All OK