U209E

DTC U209E

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.

DTC Descriptor

DTC U209E
- Object Detection Control Module High Speed Communication Enable Circuit 1

For symptom byte information, refer to Symptom Byte List Symptom Byte List.

Diagnostic Fault Information






Circuit/System Description

The active safety control module activates the object detection ignition circuit, when the ignition is ON. The object detection ignition circuit wakes up the devices for serial data bus communication.

Conditions for Running the DTC

* The system voltage is between 9-16 V.

* The vehicle power mode master requires serial data communication to occur.

Conditions for Setting the DTC

The active safety control module senses a short to ground on the object detection ignition circuit.

Action Taken When the DTC Sets

The device(s) is never signaled. Therefore, the specific subsystem(s) will not function.

Conditions for Clearing the DTC

A current DTC clears when the malfunction is no longer present.

Reference Information

Schematic Reference

* Data Communication Schematics [1][2]Electrical Diagrams

* Control Module References Control Module References

Connector End View Reference

Component Connector End Views Fuel Pump and Level Sensor Assembly

Description and Operation

Data Link Communications Description and Operation Description and Operation

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 Testing

Note: Use the schematic to determine which devices are on the K124 active safety control module's ignition circuit 9 X1. Use the connector end view to identify the object detection ignition circuit terminal for each of those devices.

1. Ignition OFF, disconnect the harness connectors at an easily accessible device that shares the K124 active safety control module's ignition circuit 9 X1. Ignition ON.

2. Verify that the DTC U209E remains current.

• If the DTC becomes history
Replace the device that was just disconnected.

• If the DTC remains current

3. With the prior devices disconnected, repeat steps 1 and 2 for each device on the ignition circuit except the K124 active safety control module.

4. Ignition OFF, disconnect the X1 harness connector at the K124 active safety control module.

5. Test for infinite resistance between the ignition circuit terminal 9 X1 at the K124 active safety control module and ground.

• If less than infinite resistance
Repair the short to ground on the circuit.

• If infinite resistance

6. Replace the K124 active safety control module.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* GMLAN Wiring Repairs GMLAN Wiring Repairs

* Control Module References Control Module References for device replacement, programming and setup