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 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 Integrated Dual Charge Module (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 (D284) CAN FD (+) CIRCUIT AND (D285) CAN FD (-) CIRCUITS FOR A SHORT TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the IDCM harness connector containing the circuits being tested.
3. Turn the ignition on.
4. Measure voltage on the (D284) CAN FD (+) circuit at the IDCM harness connector.
5. Measure voltage on the (D285) CAN FD (-) circuit at the IDCM harness connector.
  Is the voltage above 2.5 Volts on the (D284) CAN FD (+) circuit or (D285) CAN FD (-) circuit?
  
  Yes
  - Repair the (D284) CAN FD (+) circuit or (D285) CAN FD (-) circuit for a short to voltage.
  - Perform the INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST. Refer to INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST .
  No
  - Go To 3
CHECK THE (D284) CAN FD (+) CIRCUIT AND (D285) CAN FD (-) CIRCUITS FOR AN OPEN
1. Turn the ignition off.
2. Disconnect the Hybrid Control Processor (HCP) Module harness connector containing the circuits being tested.
3. Measure the resistance of the (D284) CAN FD (+) circuit between the IDCM harness connector and the HCP Module harness connector.
4. Measure the resistance of the (D285) CAN FD (-) circuit between the IDCM harness connector and the HCP Module harness connector.
  Is the resistance above 3.0 Ohms for the (D284) CAN FD (+) circuit or (D285) CAN FD (-) circuit?
  
  Yes
  - Repair the (D284) CAN FD (+) circuit or (D285) CAN FD (-) circuits for an open.
  - Perform the INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST. Refer to INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST .
  No
  - Go To 4
CHECK THE (D284) CAN FD (+) CIRCUIT AND (D285) CAN FD (-) CIRCUITS FOR A SHORT TO GROUND
1. Check for continuity between ground and the (D284) CAN FD (+) circuit at the IDCM harness connector.
2. Check for continuity between ground and the (D285) CAN FD (-) circuit at the IDCM harness connector.
  Is there continuity between the (D284) CAN FD (+) circuit or (D285) CAN FD (-) circuit?
  
  Yes
  - Repair the (D284) CAN FD (+) circuit or (D285) CAN FD (-) circuits for a short to ground.
  - Perform the INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST. Refer to INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST .
  No
  - Go To 5
CHECK THE (D284) CAN FD (+) CIRCUIT AND (D285) CAN FD (-) CIRCUITS FOR A SHORT TOGETHER
1. Check for continuity between the (D284) CAN FD (+) circuit and (D285) CAN FD (-) circuits at the IDCM harness connector.
  Is there continuity between the (D284) CAN FD (+) circuit and (D285) CAN FD (-) circuits?
  
  Yes
  - Repair the (D284) CAN FD (+) circuit and (D285) CAN FD (-) circuits for a short together.
  - Perform the INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST. Refer to INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST .
  No
  - Go To 6
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect all 12 Volt IDCM harness connectors.
2. Disconnect all related 12 Volt in-line harness connections (if equipped).
3. Disconnect the related 12 Volt component harness connectors.
4. Inspect 12 Volt harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Perform a terminal drag test on each connector terminal to verify proper terminal tension.
  Repair any conditions that are found.
5. Reconnect all IDCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase DTCs.
9. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
10. 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
  - The wiring or poor connection problem has been repaired.
  - Perform the INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST. Refer to INTEGRATED DUAL CHARGE MODULE (IDCM) VERIFICATION TEST .