2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 852

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 852

- Control Module Communication Bus B Off

DTC U180F

- Control Module Communication Bus B Off

Circuit/System Description

The PTLAN serial data circuits are serial data buses used to communicate information between the control modules. The PTLAN serial data

circuits also connect directly to the data link connector (DLC) for programming purposes. If this serial data system is inoperative the modules will

still communicate with the scan tool due to other serial data systems but not with each other. Communication with the scan tool for the modules on

the PTLAN bus is through the serial data gateway module (SDGM) on the HSGMLAN serial data system.

Conditions for Running the DTCs

* Supply voltage to the modules are in the normal operating range.

* The ignition switch in any position other than START.

Conditions for Setting the DTC

The module setting the DTC has attempted to establish communications on the PTLAN serial data circuits more than 3 times.

Action Taken When the DTCs Sets

* The module suspends all message transmission.

* The MIL and battery indicators will illuminate, along with several DIC messages.

* The vehicle may continue to run for several minutes, then will stall and not start.

Conditions for Clearing the DTC

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

* A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.

Reference Information

Schematic Reference

* Data Communication Schematics (See: Powertrain Management/Computers and Control Systems/Information Bus/Diagrams/Electrical

Diagrams)

* Control Module References (See: Testing and Inspection/Programming and Relearning)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Data Link Communications Description and Operation (See: Powertrain Management/Computers and Control Systems/Information

Bus/Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Circuit/System Testing

Verify that DTC U0074 is not set.

If the DTC is set, refer to DTC U0074 (See: U Code Charts/U0074)

Antilock Brake System - Non-Hybrid Less than 3900 kg (8600 lb) GVW

DTC C0131

Diagnostic Instructions