Diagnostic Test

WARNING: This page is about a different car, the 2017 RAM 2500 HD. 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 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 HVAC Module DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2
  No
  - Perform the TESTING FOR AN INTERMITTENT CONDITION procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
CHECK THE (C56) BLOWER CONTROL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the Blower Module harness connector.
3. Disconnect the HVAC Module C1 harness connector.
4. Measure the resistance between ground and the (C56) Blower Control circuit. Check for continuity between ground and the (C56) Blower Control circuit at the Blower Module harness connector.
  Is there continuity between ground and the circuit?
  
  Yes
  - Repair the (C56) Blower Control circuit for an short to ground.
  - Perform the HVAC VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Go To 3
CHECK THE (C56) BLOWER CONTROL CIRCUIT FOR AN OPEN
1. Turn the ignition off.
2. Measure the resistance of the (C56) Blower Control circuit between the HVAC Module C1 harness connector and the Blower Module harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the (C56) Blower Control circuit for an open.
  - Perform the HVAC VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK THE (Z911) GROUND CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Using a 12-volt test light connected to 12 volts, test the (Z911) Ground circuit at the Blower Module harness connector.
  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
  - Repair the (Z911) Ground circuit for an open or high resistance.
  - Perform the HVAC VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Go To 5
REPLACE THE BLOWER MODULE AND RECHECK DTCS
1. Replace the Blower Module in accordance with the Service Information. Refer to MOTOR, BLOWER, REMOVAL .
2. Perform the HVAC VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  Did the DTC return?
  
  Yes
  - Go To 6
  No
  - The new Blower Module repaired the problem.
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect all HVAC Module 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 HVAC Module 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 HVAC Module DTCs.
  Did the DTC return?
  
  Yes
  - Replace the HVAC Module in accordance with the Service information. Refer to MODULE, HVAC, REMOVAL .
  - Perform the HVAC VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - The wiring or poor connection problem has been repaired.
  - Perform the HVAC VERIFICATION TEST. Refer to STANDARD PROCEDURE .