Radio Controls Malfunction (with Monochrome Display)
Radio Controls Malfunction (with Monochrome Display)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
Circuit/System Description
Display RPO UFD
The radio info display and radio controls are combined into an assembly. The assembly is supplied battery voltage and ground. The radio uses the wake up circuit to control the power state of the display. The radio controls communicate inputs internally to the display. Display backlighting dimming level, graphical data, and radio control inputs are communicated over the CGI data circuits between the display and the radio.
Display RPO UAG
The radio controls and information display are separate components from the radio. Each component is supplied battery voltage and ground. The radio uses the wake up circuit to control the power state of the display. The radio controls communicate with the info display module through the LIN serial data circuit. Display backlighting dimming level, graphical data, and radio control inputs are communicated over the CGI data circuits between the display and the radio.
Reference Information
Schematic Reference
Radio/Navigation System Schematics Radio/Navigation System Schematics
Connector End View Reference
Component Connector End Views Sunshade - Left (DH6)
Description and Operation
Radio/Audio System Description and Operation (with Color Display) Radio/Audio System Description and Operation (with Color Display)Radio/Audio System Description and Operation (with Monochrome Display) Radio/Audio System Description and Operation (with Monochrome Display)
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
Display RPO UFD
1. Verify no DTCs are set as current.
• If any DTCs are set as current, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
2. Ignition ON, radio ON, verify the info display module turns on and information is shown on the display.
• If the info display is inoperative, refer to Radio Information Display Malfunction - DTC U0257 (with Color Display) DTC U0257 (with Color Display)Radio Information Display Malfunction - DTC U0257 (with Monochrome Display) DTC U0257 (With Monochrome Display).
3. Verify the radio controls backlighting illuminates and that all controls perform the correct function.
• If some, or all, of the radio controls do not operate normally, replace the A22 radio controls.
Display RPO UAG
1. Verify no DTCs are set as current.
• If any DTCs are set as current, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
2. Ignition ON, radio ON, verify the radio controls backlighting illuminates and that all controls perform the correct function.
• If some, but not all, controls operate normally, replace the A22 radio controls.
• If all controls are inoperative, refer to Circuit/System Testing.
Circuit/System Testing
Display RPO UAG
1. Ignition OFF, disconnect the harness connector at the A22 radio controls.
2. Test for less than 10 ohms between the ground circuit terminal 3 and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Verify that a test lamp illuminates between the B+ circuit terminal 1 and ground.
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
4. Ignition ON, test for 2-11.5 V between the data circuit terminal 2 and ground.
• If less than the specified range, test the data circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the P17 info display module.
• If greater than the specified range, test the data circuit for a short to voltage. If the circuit tests normal, replace the P17 info display module.
5. If all circuits test normal, replace the A22 radio controls.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Driver Information Display Replacement (UAG) Driver Information Display Replacement (UAG)Driver Information Display Replacement (UDY) Driver Information Display Replacement (UDY)
* Control Module References Control Module References for radio control assembly replacement, setup, and programming