U1811

DTC U1811

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 U1811 00
- Battery Energy Control Module Powertrain Expansion CAN Bus Off Malfunction

Circuit/System Description

The powertrain high speed GMLAN serial data circuits are serial data buses used to communicate information between the devices.

This diagnostic is used to check the powertrain high speed GMLAN communication bus status.

Conditions for Running the DTC

* The ignition is ON.

* The system voltage is greater than 8.8 V.

Conditions for Setting the DTC

The device setting the DTC has attempted to establish communications on the serial data circuits for more than 1.4 seconds without success.

Action Taken When the DTC Sets

The DTC U1811 is a type B DTC.

Conditions for Clearing the DTC

The DTC U1811 is a type B DTC.

Reference Information

Schematic Reference

Data Communication Schematics [1][2]Electrical Diagrams

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

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool References

Control Module References Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify DTC U1811 is not set.

• If DTC U1811 is set
Refer to DTC U0074 (Chassis Expansion Bus) Data Communications (Chassis Expansion Bus)DTC U0074 (Powertrain Expansion Bus) Data Communications (Powertrain Expansion Bus).

• If DTC U1811 is not set

3. All OK