Diagnostic Test

WARNING: This page is about a different car, the 2024 RAM ProMaster EV. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR AN ACTIVE DTC
1. With the scan tool, read Body Control Module (BCM) DTCs and record on the repair order.
2. Record the Environmental Data.
3. With the scan tool, erase DTCs.
4. With the Engine off and the Park Brake firmly applied, shift the Gear Selector to the REVERSE position.
5. With the scan tool, read BCM DTCs.
  Did the DTC return?
  
  Yes
  - Go To Next Step.
  No
  - Perform the TESTING FOR INTERMITTENT CONDITIONS procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
CHECK THE (L27) LEFT FRONT PARK/DRL LAMP CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
1. Shift the Gear Selector to the PARK position.
2. Turn the ignition off.
3. Disconnect the related BCM connector and the left headlamp connector.
4. Turn the ignition on.
5. Measure the voltage on the Left Front Park/DRL Lamp Control circuit at the front head lamp connector
  Is there any voltage present?
  
  Yes
  - Repair the short to voltage in the Left Front Park/DRL Lamp Control circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To Next Step.

LOAD TEST THE (Z906) HEADLAMP GROUND CIRCUITS

Read the CIRCUIT LOAD TESTING PROCEDURE for information on building a simple load test tool, additional load testing information and alternative methods of load testing or voltage drop testing a circuit. Refer to CIRCUIT LOAD TESTING PROCEDURES .

Disconnect the Headlamp harness connector to isolate the ground circuit.

Connect the positive lead of the load test tool to the positive side of the Battery and connect the negative lead of the load test tool to the ground circuit at the Headlamp harness connector (A).

Courtesy of CHRYSLER GROUP, LLC

The bulb on the load test tool should be illuminated and bright if there is no resistance in either circuit. Compare the brightness of the bulb in the load test tool to that of a direct connection to battery.
NOTE:
To verify with certainty that the circuit is good, perform a simple voltage drop test across the 3156 bulb of the load test tool.

NOTE:
A 12-volt test light can be substituted for the load test tool, but only if the test light draws enough current to effectively load test the circuit. Many high impedance test lights draw very little amperage (less than 0.1 amps) and are not reliable to load test a circuit. To perform a proper load test of a circuit, the tool being used should draw more than approximately 0.75 amps.

Is the load test bulb illuminated and bright?

Yes
- Go To Next Step
No
- Repair the ground circuit for an open or high resistance.
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

CHECK THE (L27) LEFT FRONT PARK/DRL LAMP CONTROL CIRCUIT FOR AN OPEN
1. Turn the ignition off.
2. Disconnect the related BCM harness connector.
3. Measure the resistance of the Left Front Park/DRL Lamp Control circuit between the BCM harness connector and the Front Head Lamp Connector.
  Is the resistance above 3.0 Ohms for any of the connections?
  
  Yes
  - Repair the open in the Left Front Park/DRL Lamp Control circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To Next Step.
CHECK THE BCM LEFT FRONT PARK/DRL LAMP OUTPUT
1. Turn the ignition on.
3. Connect a 12-volt test light between ground and the Left Front Park/DRL Lamp Control circuit
  Does the test light illuminate brightly for all connections?
  
  Yes
  - Replace the Left Headlamp assembly in accordance with service information. Refer to UNIT, FRONT LAMP, REMOVAL AND INSTALLATION .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To Next Step.
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect all BCM harness connectors.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. Inspect 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 BCM 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 BCM DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Body Control Module (BCM) in accordance with the Service Information. Refer to MODULE, BODY CONTROL (BCM), REMOVAL AND INSTALLATION .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  - Test complete.