Diagnostic Test

WARNING: This page is about a different car, the 2025 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR AN ACTIVE DTC
WARNING:
On vehicles equipped with the high voltage system, you must thoroughly read and follow all High Voltage Safety procedures. In addition, before performing any diagnostic or service procedure near a high voltage component, you must perform the High Voltage Power Down. Failure to follow these instructions may result in possible serious or fatal injury.

Read the HIGH-VOLTAGE SAFETY PROCEDURES. Refer to HIGH VOLTAGE SAFETY PROCEDURES .

When the HIGH-VOLTAGE POWER-DOWN PROCEDURE is necessary. Refer to HIGH VOLTAGE POWER DOWN .
1. With the scan tool, read Integrated Dual Charge Module (IDCM) DTCs and record on the repair order.
2. Record the Environmental Data, Snap-Shot Data and any DTCs.
3. With the scan tool, erase DTCs.
4. Using the recorded Environmental Data and Snap-Shot Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
5. With the scan tool, read IDCM DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2
  No
  - Perform the TESTING FOR AN INTERMITTENT CONDITION diagnostic procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
CHECK THE 12.0 VOLT BATTERY STATE OF CHARGE (SOC)
1. Using the approved Mopar® Battery Tester/Charger Station, test the 12.0 Volt Battery.
  Did the 12.0 Volt Battery pass the load test?
  
  Yes
  - Go To 3
  No
  - Follow the repair on the tester and charge or replace the 12.0 Volt Battery in accordance with the Service Information. Refer to BATTERY, REMOVAL AND INSTALLATION .
  - Perform the INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST. Refer to INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST .
CHECK FOR VOLTAGE ON THE (A357) B(+) CIRCUIT
1. Turn the ignition off.
2. Disconnect the IDCM C6 harness connector.
3. Measure the voltage on the (A357) B(+) circuit at the IDCM.
  Is the voltage above 10.0 volts?
  
  Yes
  - Go To 5
  No
  - Go To 4
CHECK THE (A357) B(+) CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Disconnect the Post Pass-Through harness connector.
2. Measure the resistance of the (A357) B(+) circuit between the IDCM and the Post Pass-Through harness connector.
  Is the resistance above 3.0 Ohms?
  
  Yes
  - Repair the (A357) B(+) circuit for an open or high resistance.
  - Perform the INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST. Refer to INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST .
  No
  - Go To 5
CHECK FOR LOOSE CONNECTOR TERMINALS AND POOR CONNECTIONS
1. Inspect the following for loose connector terminals and poor connections and repair if needed:
  - 12.0 volt Battery (+) and (-) terminals
  - (A357) B(+) circuit at the IDCM
  - (Z908) Ground circuit at the IDCM
  - (A357) B(+) at the Post Pass-Through harness connector
2. With the scan tool, erase DTCs.
3. Using the recorded Environmental Data and Snap-Shot Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
4. With the scan tool, read IDCM DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Integrated Dual Charge Module (IDCM) in accordance with the Service Information. Refer to MODULES, HIGH VOLTAGE SYSTEM, REMOVAL AND INSTALLATION .
  - Perform the INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST. Refer to INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST .
  No
  - Perform the INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST. Refer to INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST .
  - Test complete.