Diagnostic Test

CHECK FOR AN ACTIVE DTC
1. With the scan tool, read Instrument Panel Cluster (IPC) DTCs and record on the repair order.
2. Record the Environmental Data and any DTCs.
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 IPC 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 (F948) FUSED IGNITION CIRCUIT VOLTAGE
1. Turn the ignition off.
2. Disconnect the Humidity Sensor harness connector.
3. Turn the ignition on.
4. Measure the voltage of the (F948) Fused Ignition circuit at the Humidity Sensor harness connector.
  Is the voltage below 9.0 volts?
  
  Yes
  - Remove and inspect Fuse F49.
  - If Fuse Is Okay: Repair the open in the circuit and install the fuse.
  - If Fuse Is Open: Repair the short to ground in the circuit and replace the fuse.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 3
CHECK THE (Z930) GROUND CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. With a 12-volt test light connected to 12 volts, check both (Z930) Ground circuits at the Humidity Sensor 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 circuit for an open or high resistance.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 4
CHECK THE (D409) LIN BUS CIRCUIT VOLTAGE
1. Turn the ignition on.
2. Measure the voltage of the (D409) LIN Bus circuit at the Humidity Sensor harness connector.
  Is there any voltage present?
  
  Yes
  - Replace the Humidity Sensor in accordance with the Service Information. Refer to SENSOR, HUMIDITY, REMOVAL AND INSTALLATION .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 5
CHECK THE (D409) LIN BUS CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the IPC harness connector.
3. Measure the resistance of the (D409) LIN Bus circuit between the Humidity Sensor harness connector and the IPC harness connector.
  Is the resistance above 3.0 Ohms?
  
  Yes
  - Repair the circuit for an open or high resistance.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 6
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect all IPC 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 IPC 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 IPC DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Instrument Panel Cluster (IPC) in accordance with the Service Information. Refer to 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.