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Chevrolet Silverado / GMC Sierra. Manual - part 2663
1. Ignition ON, headlamps ON, vehicle in PARK, cover the front light sensor with a towel or
other suitable item. Shine a flashlight at the rear light sensor while observing the inside
rearview mirror face. The inside rearview mirror face should dim.
If the mirror face does not dim, test or replace the inside rearview mirror.
2. Headlamps ON, park brake applied, cover the front light sensor with a towel or other
suitable item. Shine a flashlight at the rear light sensor while observing the inside rearview
mirror face. Place the transmission in REVERSE. The inside rearview mirror face should
transition from dim to bright.
If the mirror does not transition from dim to bright, refer to Reverse Input Malfunction
below.
3. Remove the towel from the inside rearview mirror and remove the flashlight. Verify the
inside rearview mirror face returns to its normal bright state.
If the mirror face does not return to its normal state, test or replace the inside rearview
mirror.
Circuit/System Testing
Reverse Input Malfunction
1. Ignition OFF, disconnect the harness connector at the inside rearview mirror.
2. Ignition ON, park brake applied, vehicle in REVERSE, test for B+ between the supply
voltage circuit terminal 9 and ground.
If less than the specified value, test the supply voltage circuit for a short to ground or
an open/high resistance. If the circuit tests normal, refer to Backup Lamps
Malfunction .
3. If all circuits test normal, test or replace the inside rearview mirror.
Repair Procedures
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Inside Rearview Mirror Replacement
POWER MIRROR FOLDING INOPERATIVE
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.
2008 Chevrolet Silverado 1500
2008 ACCESSORIES & EQUIPMENT Mirrors - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
Diagnostic Procedure Instructions provides an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System Description
The Driver Door Switch (DDS) and Passenger Door Switch (PDS) control the power folding or
power extending functions of the outside rearview mirrors. The folding mirror motors are
controlled by using bi-directional motor controls through the folding mirror motor retract control
circuit and the folding mirror motor extend control circuit.
Reference Information
Schematic Reference
Outside Rearview Mirror Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Outside Mirror Description and Operation (Heated Mirrors) or Outside Mirror
Description and Operation (Power Mirrors)
Electrical Information Reference
Circuit Testing
Connector Repairs
Testing for Intermittent Conditions and Poor Connections
Wiring Repairs
Circuit/System Verification
Circuit
Short to
Ground
Open/High
Resistance
Short to
Voltage
Signal
Performance
Folding Mirror Motor Retract
Control
B1722 02
B1722 04
B1722 01
-
Folding Mirror Motor Extend
Control
B1722 02
B1722 04
B1722 01
-
2008 Chevrolet Silverado 1500
2008 ACCESSORIES & EQUIPMENT Mirrors - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
1. Ignition ON, observe the scan tool Mirror Fold Switch parameter while cycling the mirror
fold switch between the extend and retract positions. The parameter should change between
Idle, Extend, and Retract.
If the parameter does not cycle between the specified values, replace the DDS.
2. Command the power folding mirrors to extend and retract using the mirror fold switch. Both
mirrors should extend and retract as commanded.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector X7 at the appropriate door switch.
2. Ignition ON, verify a test lamp does not illuminate between the following circuit terminals
and ground:
Control circuit terminal 1
Control circuit terminal 2
If the test lamp illuminates, test the appropriate circuit for a short to voltage.
3. Ignition OFF, test for infinite resistance between the following circuits and ground:
Control circuit terminal 1
Control circuit terminal 2
If less than the specified value, test the appropriate circuit for a short to ground. If the
circuits test normal, test or replace the rearview mirror motor.
4. Test for 5-15 ohms of resistance between the control circuit terminal 1 and the control
circuit terminal 2.
If not within the specified range, test both control circuits for an open/high resistance.
If the circuits test normal, test or replace the rearview mirror motor.
5. If all circuits test normal, replace the appropriate door switch.
Repair Procedures
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Outside Rearview Mirror Motor Replacement
Control Module References for DDS or PDS replacement, setup, and programming
POWER MIRRORS INOPERATIVE
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
2008 Chevrolet Silverado 1500
2008 ACCESSORIES & EQUIPMENT Mirrors - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
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/System Description
The Driver Door Switch (DDS) or Passenger Door Switch (PDS) controls the mirror horizontal
and vertical motors through the use of bi-directional motor controls. When the mirror is
commanded up, voltage is supplied to the mirror vertical motor through the Driver/Passenger
Mirror Motor Right/Down Motors Common circuit and ground is supplied through the
Driver/Passenger Mirror Motor Down Control circuit. When the mirror is commanded down,
voltage is supplied to the mirror vertical motor through the Driver/Passenger Mirror Motor Down
Control circuit and ground is supplied through the Driver/Passenger Mirror Motor Right/Down
Motors Common circuit.
Horizontal controls operate in the same manner with the Driver/Passenger Mirror Motor
Right/Down Motors Common circuit supplying voltage and the Driver/Passenger Mirror Motor
Right Control circuit supply a ground to the mirror horizontal motor when the mirror is
commanded right. When the mirror is commanded left, voltage is supplied to the mirror
horizontal motor through the Driver/Passenger Mirror Motor Right Control circuit and ground is
Circuit
Short to
Ground
Open/High
Resistance
Short to
Voltage
Signal
Performance
5-Volt Reference
B1580,
B1590
B1580, B1590
B1580,
B1590
-
Driver/Passenger Mirror
Horizontal Position Sensor
Signal
B1580
B1580
B1580
-
Driver/Passenger Mirror
Vertical Position Sensor Signal
B1590
B1590
B1590
-
Driver/Passenger Mirror Motor
Right Control
B1605 02
B1605 04
B1605 01
-
Driver/Passenger Mirror
Right/Down Motors Common
B1544 02
B1544 04
B1544 01
-
Driver/Passenger Mirror Motor
Down Control
B1600 02
B1600 04
B1600 01
-
Low Reference
B1580,
B1590
B1580, B1590
B1580,
B1590
-
2008 Chevrolet Silverado 1500
2008 ACCESSORIES & EQUIPMENT Mirrors - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
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