Diagnostic Test

Read And Record DTCS And Environmental Data - Erase DTCS And Check For DTC To Return
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. With The Scan Tool, Read The Active Radio DTCS.
NOTE:
A Front Door Must Remain Open Whenever Checking Or Erasing Radio DTCS.

Did The DTC Return?

Yes
- Go To 2
No
- Test Complete, The Condition Or Conditions That Originally Set This DTC Are Not Present At This Time. Using The Appropriate System Wiring Diagrams As A Guide, Check All Related Splices And Connectors For Signs Of Water Intrusion, Corrosion, Pushed Out Or Bent Terminals And Correct Pin Tension.
- Perform The Body Verification Test. Refer To Body Verification Test .
Determine The Vehicle Configuration
1. Review The Vehicle Sales Codes To Determine The Vehicle Audio System Configuration.
  Is The Vehicle Equipped With Sales Code RFV - Disassociated Touchscreen Display?
  
  Yes
  - Go To 4
  No
  - Go To 3
Verify Operation Of The Button
1. With The Scan Tool, Read DTCS And Record On Repair Order.
2. With The Scan Tool, Erase DTCS.
3. Press And Release All The Radio Hard And Soft Keys Three Times.
4. Wait 60 Seconds.
5. With The Scan Tool, Read DTCS.
  Did The DTC Return?
  
  Yes
  - Replace The Radio In Accordance With The Service Information. Refer To Module, Radio Receiver, Removal And Installation .
  - Perform The Body Verification Test. Refer To Body Verification Test .
  No
  - Test Complete.
  - Perform The Body Verification Test. Refer To Body Verification Test .
Check The Integrated Center Stack (ICS)
1. With The Scan Tool, Read The ICS DTCS.
  NOTE:
  The ICS Is Capable Of Setting A Similar Type DTC For B157F-2A-Button/Knob - Stuck
  
  Does The ICS Have DTCS?
  
  Yes
  - Refer To - Dtc-Based Diagnostics/Module, Integrated Center Stack (ICS) Diagnosis And Testing.
  No
  - Go To 5
Check The Steering Column Control Module (SCCM)
1. With The Scan Tool, Read The SCCM DTCS.
  NOTE:
  The SCCM Is Capable Of Setting A Similar Type DTC For B1425-2A-Remote Radio Switch Input - Stuck
  
  Does The SCCM Have DTCS?
  
  Yes
  - Refer To - Dtc-Based Diagnostics/Module, Steering Column Control) Diagnosis And Testing.
  No
  - Go To 6
Check The ICS And Steering Wheel Switch Buttons
1. Carefully Check The ICS And Steering Wheel Switch Buttons By Pressing And Releasing Each Button For The Following:
  - Debris (Dirt, Foreign Objects, Sticky Substances, Etc.) That May Be Causing The Button(S) To Remain In A Pressed State.
  - Physical Damage To The Buttons.
  Do The Buttons Show Any Of The Above Noted?
  
  Yes
  - If Needed - Replace The ICS In Accordance With The Service Information. Refer To Module, Integrated Center Stack (ICSM), Removal And Installation .
  - If Needed - Replace The Steering Wheel Switches In Accordance With The Service Information. Refer To Switch, Remote Radio, Removal And Installation .
  - Perform The Body Verification Test. Refer To Body Verification Test .
  No
  - Go To 7
Check The Radio Bussed Inputs
1. Do Not Press Any Buttons In Or On The Vehicle During This Portion.
2. With The Scan Tool, Check The Radio Data Tab For Each Bussed Input Value / Status For The Following:
  NOTE:
  Those Bussed Inputs To The Radio With A SWS Designation Originate From The Steering Wheel Switches On Lin Bus To The SCCM. The Other Bussed Inputs Are Through The Integrated Center Stack.
  - Pressed Or Not Pressed (ICS)
  - Active Or Not Active (SCCM)
  Does The Scan Tool Show A "Pressed" Or "Active" Bussed Input Value / Status In The Radio Data?
  
  Yes
  - Go To 8
  No
  - Go To 9
Check The Associated ECU
1. Turn The Ignition Off.
2. Based On The Information Found In Step, Remove The Related ECU Found From Communicating On The Can Bus To Confirm As The Possible Cause: Refer To 7.
  NOTE:
  An ECU Will Stop Communicating On A Can Bus By Removing Its Power(S), Ground(S), Or Disconnecting The ECU.
  - ICS - Integrated Center Stack
  - SCCM - Steering Column Control Module
  NOTE:
  Communication DTCS (I.E. Loss Of Com, Implausible, Invalid) May Appear For Those ECUS That Are Removed From Communicating On The Can Bus.
3. Turn The Ignition On
4. With The Scan Tool, Check The Radio Data Tab For Each Bussed Input Value / Status For The Following:
  NOTE:
  Those Bussed Inputs To The Radio With A SWS Designation Originate From The Steering Wheel Switches On Lin Bus To The SCCM. The Other Bussed Inputs Are Through The Integrated Center Stack.
  - Pressed Or Not Pressed (ICS)
  - Active Or Not Active (SCCM)
  Did The Bussed Input Value / Status In The Radio Data Change To "Not Pressed" Or "Not Active"?
  
  Yes
  - Replace The Related ECU In Accordance With Service Information
    - For The ICS. Refer To Module, Integrated Center Stack (ICSM), Removal And Installation .
    - For The SCCM. Refer To Module, Steering Column Control (SCCM), Removal And Installation .
    - Perform The Body Verification Test. Refer To Body Verification Test .
  No
  - Replace The Radio In Accordance With The Service Information. Refer To Module, Radio Receiver, Removal And Installation .
  - Perform The Body Verification Test. Refer To Body Verification Test .
Check The Associated ECUS For Possible Cause
1. Turn The Ignition Off.
2. The Following ECUS Listed Below Will Need To Be Removed (One At A Time ) From Communicating On The Can Bus To Determine The ECU As The Possible Cause:
  NOTE:
  An ECU Will Stop Communicating On A Can Bus By Removing Its Power(S), Ground(S), Or Disconnecting The ECU.
  - ICS - Integrated Center Stack
  - SCCM - Steering Column Control Module
  NOTE:
  Communication DTCS (I.E. Loss Of Com, Implausible, Invalid) May Appear For Those ECUS That Are Removed From Communicating On The Can Bus.
3. Turn The Ignition On
4. With The Scan Tool, Check The Radio Data Tab For Each Bussed Input Value / Status For The Following:
  NOTE:
  Those Bussed Inputs To The Radio With A SWS Designation Originate From The Steering Wheel Switches. The Other Bussed Inputs Are Through The Integrated Center Stack.
  - Pressed Or Not Pressed
  - Active Or Not Active (SWS Related Only)
5. Repeat The Above Sub Steps 1 - 4 Of Step 9 For The Remaining ECU.
  Which ECU When Disconnected Changed The "Pressed" Or "Active" Bussed Input Value / Status In The Radio Data To "Not Pressed" Or "Not Active"?
  
  ICS
  - Replace The ICS In Accordance With The Service Information. Refer To Module, Integrated Center Stack (ICSM), Removal And Installation .
  - Perform The Body Verification Test. Refer To Body Verification Test .
  SCCM
  - 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 .
  Neither
  - Replace The Radio In Accordance With The Service Information. Refer To Module, Radio Receiver, Removal And Installation .
  - Perform The Body Verification Test. Refer To Body Verification Test .