Chevrolet Silverado / GMC Sierra. Service manual - part 2963

Circuit/System Description

The body control module (BCM) monitors the window lockout command from the driver door
switch (DDS). When the rear window switch operation is authorized, the the BCM signal voltage
drops approximately 5 volts to the rear window switches allowing for normal window operation
from the rear switches. If the rear window lockout function is commanded, the BCM signal
voltage is at B+ voltage which disables the rear window switches and the rear windows will only
operate when the BCM receives a command from the driver master control.

Conditions for Running the DTC

Battery voltage is between 9-16 volts.

Rear Down Signal
Power Window Switch Right
Rear Up Signal

B3822 00

Power Window Switch Left
Rear Down Signal

B3820 00

Power Window Switch Left
Rear Up Signal

B3819 00

Power Window Lockout Left
Rear Control

B3821 00

Power Window Lockout Right
Rear Control

B3824 00

LR Window Motor Control

Passenger Window Motor
Control

B3205 00

B3205 0B

B3205 00

RR Window Motor Control

Driver Window Motor
Control

B3205 00

B3205 0B

B3205 00

LR Window Switch Ground

RR Window Switch Ground

Driver Door Switch Ground

U0199 00

Passenger Door Switch
Ground

U0200 00

1. Driver Window Malfunction
2. Passenger Window Malfunction
3. Left Rear Window Malfunction
4. Right Rear Window Malfunction

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Fixed and Moveable Windows - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

The ignition is ON.

Conditions for Setting the DTC

B3821 00

The BCM detects a fault in the left rear window lockout circuit.

B3824 00

The BCM detects a fault in the right rear window lockout circuit.

Action Taken When the DTC Sets

The left or right rear power window will be inoperative.

Conditions for Clearing the DTC

The DTC will be current for as long as the fault is present.

When the fault is no longer present, the DTC will be a history DTC.

A history DTC will clear after 50 ignition cycles

Reference Information

Schematic Reference

Moveable Window Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Power Windows Description and Operation

Electrical Information Reference

Circuit Testing

Connector Repairs

Testing for Intermittent Conditions and Poor Connections

Wiring Repairs

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Fixed and Moveable Windows - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Ignition ON, command the rear windows UP and DOWN by using the window switches on the
driver master control and their respective rear window switches. The rear windows should
perform the UP and DOWN function from each switch.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the appropriate rear window switch.

2. Ignition ON, with the rear window switches enabled, test for more than 10 volts between

the control circuit terminal D and ground.

If less than the specified range, test the control circuit for a short to ground or
open/high resistance. If the circuit tests normal, replace the BCM

3. If all circuits test normal, replace the rear window switch.

Repair Procedures

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Rear Side Door Window Switch Replacement (Crew Cab) or Rear Side Door
Window Switch Replacement (Extended Cab)

Control Module References for BCM replacement, setup and programming

SYMPTOMS - FIXED AND MOVEABLE WINDOWS

1. Perform the Diagnostic System Check - Vehicle before using the Symptom Tables in

order to verify that all of the following are true:

There are no DTCs set.

The control modules can communicate via the serial data link.

2. Review the system operation in order to familiarize yourself with the system functions.

Refer to the following system descriptions:

Power Windows Description and Operation

IMPORTANT: The following steps must be completed before using the symptom

tables.

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Fixed and Moveable Windows - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

Rear Window Defogger Description and Operation

Visual/Physical Inspection

Inspect for aftermarket devices which could affect the operation of the system. Refer to
Checking Aftermarket Accessories .

Inspect the easily accessible or visible system components for obvious damage or conditions
which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to
Testing for Intermittent Conditions and Poor Connections .

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the
symptom:

Rear Window Defogger Malfunction

Power Windows Malfunction (A31/AN3/DL3) or Power Windows Malfunction (A31
w/o AN3, DL3)

Power Rear Sliding Window Malfunction

REAR WINDOW DEFOGGER MALFUNCTION

Diagnostic Instructions

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Review Strategy Based Diagnosis for an overview of the diagnostic approach.

Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to

Ground

Open/High

Resistance

Short to

Voltage

Signal

Performance

Relay Switch B+

Rear Defog Relay Control

B0283 06

Rear Defog Relay Ground

B0283 06

Rear Defogger Control

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Fixed and Moveable Windows - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

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