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. Using the recorded Environmental 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 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 (W3) WIPER LOW SPEED CONTROL OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
NOTE:
Verify the Front Wipers are off when performing this step.
1. Turn the Front Wipers off.
2. Turn the ignition off.
3. Disconnect the Front Wiper Motor harness connector.
4. Turn the ignition on.
5. Measure the voltage on the Front Wiper Low Speed Control Output circuit at the Front Wiper Motor harness connector.
  Is there any voltage present?
  
  Yes
  - Repair the short to voltage in the Front Wiper Low Speed Control Output circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To Next Step.
LOAD TEST THE (A6) POWER SUPPLY AND (Z909) GROUND CIRCUIT TO THE WIPER MOTOR
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 .
1. Disconnect the Wiper Motor harness connector.
2. Connect one lead of the load test tool to the power supply circuit and the other lead of the load test tool to the ground circuit.
3. Ensure that the power supply circuit is being powered on.
4. If there is no resistance in either circuit the bulb on the load test tool should be illuminated and bright. 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. The voltage drop across the bulb should be equal to the voltage reading across the battery terminals if there is no resistance in either circuit.
  
  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
  - If the circuits fail the load test, remove the lead connected to the ground circuit and connect it to a good chassis ground. Check the bulb illumination and voltage drop across the 3156 bulb of the load test tool again. If the bulb is not bright or the voltage drop is still less than battery voltage, repair the battery supply circuit for an open or high resistance. If the bulb is bright or the voltage drop is now equal to battery voltage, repair the ground circuit for an open or high resistance.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE BCM FOR CORRECT OPERATION
1. Turn the Front Wipers off.
2. Turn the ignition off.
3. Connect a 12-volt test light between ground and the Front Wiper Low Speed Control Output circuit at the Front Wiper Motor harness connector.
4. Turn the ignition on.
5. Turn the Front Wipers on LOW.
  NOTE:
  The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
  
  Does the test light illuminate brightly?
  
  Yes
  - Replace the Front Wiper Motor in accordance with the Service Information Refer to WIPER LINKAGE ARM .
  - 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.