2010 Cadillac Truck Escalade RWD V8-6.2L Page 2750

2010 Cadillac Truck Escalade RWD V8-6.2L Page 2750

Circuit/System Verification

Verify that U0102 is not set.

If the DTC is set, refer to DTC U0100-U02FF (with HP2) ()DTC U0100-U02FF (without HP2) (See: U Code Charts/U02FF)

U186B

DTC U186B

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC U186B

- Lost Communication With TCM

Circuit/System Description

Modules connected to the serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and

commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be exchanged on the

serial data circuits, for each virtual network. The messages are supervised and also, some periodic messages are used by the receiver module as an

availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

Conditions for Running the DTCs

* The system voltage is between 9-16 volts.

* The vehicle power mode master indicates that the need for serial data communications.

Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTCs Sets

The modules is never signaled, therefore the specific subsystems will not function.

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.

Circuit/System Verification

Verify that U0101 is not set.

If the DTC is set, refer to DTC U0100-U02FF (with HP2) ()DTC U0100-U02FF (without HP2) (See: U Code Charts/U02FF)

U189A

DTC U189A

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.