Diagnostic Test

1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
2. With the scan tool, run a vehicle Scan Report, or record the Environmental Data related to the DTCs.
3. NOTE: A front door must remain open whenever checking or erasing Radio DTCs. 
4. With the scan tool, record and erase the Radio DTCs.
5. Cycle the ignition switch from on to off, wait five seconds and then back to on.
6. Turn the Radio on and set the volume to 25.
7. Adjust the speakers to the front and center.
8. With the scan tool, read the active Radio DTCs.

Did the DTC return?

Yes 

• Go To  2

No 

• Perform the appropriate INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .

1. Do not press either remote radio switch.
2. Hands off the Steering Wheel.
3. With the scan tool, monitor the "PRESSED/NOT PRESSED" status of the remote radio switches in the Radio data display.

   Do any remote radio switch always show "PRESSED"?

   Yes 

   • Go To  3

   No 

   • Replace the Radio in accordance with the Service information. Refer to RADIO, REMOVAL AND INSTALLATION .
   • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

1. Start the engine and allow it to idle.
2. With the scan tool, continuously monitor the "PRESSED/NOT PRESSED" status of the remote radio switches in the Radio data display while performing the test in the following order:
   • Hands on the Steering Wheel turning slowly to full left, full right, and back to center.
   • Hands on the Steering Wheel apply slight straight ahead pressure while turning slowly to full left, full right, and back to center.
   • Hands on the Steering Wheel pulling back with slight pressure while turning slowly to full left, full right, and back to center.
   • If equipped, adjust the steering column up and down in all positions, and repeat the above process.
3. Turn the engine off.

   Did the remote radio switch status change during testing?

   Yes 

   • Go To  4

   No 

   • Go To  7

1. The ignition must be off when checking the circuit for damage.
2. Using the wiring diagram, isolate the LIN Bus circuit by disconnecting the Electronic Control Unit (ECU) and every component harness connector containing the circuit. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
3. Inspect the LIN Bus circuit for chafed, pierced, pinched, or partially broken wires.
4. Inspect the LIN Bus connectors and terminals for broken, bent, pushed out, spread, corroded, contaminated or the presence of foreign conductive materials on connector pins and terminals.

   Was any visual damage found to the LIN Bus circuit?

   Yes 

   • Repair the damaged circuit as needed.
   • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

   No 

   • Go To  5

1. The ignition must be off when checking a circuit for continuity to ground.
2. Connect the negative lead of the DVOM to a known good ground.
3. With the positive lead of the DVOM, probe the circuit being tested at the component harness connector and check for continuity between the circuit and ground.

Is there continuity between ground and the circuit being tested?

Yes 

• Repair the circuit for a short to ground. Use the wiring diagram as a guide to trace the circuit and look for any in-line connectors to help isolate the location of the short.
• Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

No 

• Go To  6

1. The ignition must be off when performing a resistance check to find a short between circuits.
2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and every component harness connector containing the circuit being tested. At this time leave all in-line connectors connected. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
3. Connect one lead of the DVOM to the circuit being tested at the ECU harness connector.
4. With the other lead of the DVOM probe all other circuits at the ECU harness connector.

Is there continuity between the circuit being tested and any other circuit?

Yes 

• Repair the short between the circuits that have continuity. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors to help isolate the location of the short.
• Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

No 

• Go To  7

1. The ignition must be off.
2. Remove the remote radio switches from the steering wheel. Refer to SWITCH, REMOTE RADIO, REMOVAL AND INSTALLATION .
3. Use an ohmmeter to check the switch resistances as shown in the Remote Radio Switch Test chart below.

   REMOTE RADIO SWITCH TEST
   Switch	Switch Position	Minimum Resistance (kilohms)	Nominal Resistance (kilohms)	Maximum Resistance (kilohms)
   Right	Volume Up	6.732	6.8	6.868
   Right	Volume Down	14.850	15	15.151
   Right	Mode Advance	0	0	0
   Left	Seek Up	1.188	1.2	1.212
   Left	Seek Down	3.267	3.3	3.333
   Left	Pre-Set Station Advance	0.465	0.47	0.474

   Are the remote radio switch resistances in specifications?

   Yes 

   • Go To  8

   No 

   • Replace the Remote Radio Switches in accordance with Service Information. Refer to SWITCH, REMOTE RADIO, REMOVAL AND INSTALLATION .
   • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

1. Disconnect all Steering Column Control Module (SCCM) 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).
   • Presence of foreign conductive materials on connector pins and terminals.
   • 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 SCCM 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 SCCM DTCs.

    Did the DTC return?

    Yes 

    • Replace the SCCM in accordance with the Service information. Refer to MODULE, STEERING COLUMN CONTROL (SCCM), 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.