U2121

DTC U2121

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview)provides an overview of each diagnostic category.



DTC Descriptor
DTC U2121
- No Communication with Radio Display




Circuit/System Description

The radio continuously sends a communication signal to the driver information display. Upon receiving the signal, the display sends a reply signal, confirming that it can communicate. The display is directly connects to the radio with no external circuits involved.


Conditions for Running the DTC

The radio is active.


Conditions for Setting the DTC

The radio does not receive a response from the radio display for 10 or more consecutive seconds.


Action Taken When the DTC Sets

The system will set the DTC and disable itself.


Conditions for Clearing the DTC

* The current DTC will clear when the radio receives a communication reply from the driver information display.
* The history DTC will clear after 50 fault-free ignition cycles have occurred.



Diagnostic Aids

Physically check that the driver information display is correctly mounted to the radio.


Reference Information
Schematic Reference

Radio/Navigation System Schematics (Radio/Navigation System Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Radio/Audio System Description and Operation (Radio/Audio System Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning)for scan tool information


Circuit/System Verification

1. Verify that DTC U2121 is not set.

• If the DTC is set, replace the driver information display. If the DTC resets, replace the radio.




Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.


Control Module References (Programming and Relearning)for radio and driver information display replacement, setup, and programming