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Power Mirrors Inoperative (with RPO AN3)



Power Mirrors Inoperative (with RPO AN3)

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* 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 supplied through the Driver/Passenger Mirror Motor Right/Down Motors Common circuit.

On vehicles equipped with RPO DL3/DR4, the Driver Door Switch (DDS) and Passenger Door Switch (PDS) determines the position of the outside rearview mirrors based on inputs from two mirror position sensors, one for vertical position, the other for horizontal position. 5 volts is applied to each sensor through a shared 5-volt reference circuit and a shared low reference circuit supplies ground. Each sensor has an individual signal circuit which provides position voltage to the DDS/PDS.

Circuit/System Verification

1. Ignition ON, observe the scan tool Mirror Select Switch parameter while cycling the mirror select switch between the left and right positions. The parameter should change between Idle, Left, and Right.

• If the parameter does not cycle between the specified values, replace the DDS.

2. Observe the scan tool Mirror Motor parameter while cycling the mirror directional switch between the up, down, left and right positions. The parameter should change between Idle, Up, Down, Left, and Right.

• If the parameter does not cycle between the specified values, replace the DDS.

3. Verify the vehicle is equipped with RPO DL3/DR4.

• If the vehicle is not equipped with RPO DL3/DR4, refer to Mirror Motor Circuit Malfunction

4. Observe the scan tool Mirror Horizontal Position and Mirror Vertical Position parameters. The reading should be between 0.2 volt and 4.8 volts and change as the mirror is moved, left, right, up, and down.

• If not within the specified range or the parameter does not change as the mirror is moved, refer to Mirror Position Sensor Circuit Malfunction.

5. Command the left and right outside mirror to move up, down, left and right using the mirror directional switch. The mirrors should move in the commanded direction.

• If either mirror does not move in all commanded directions, refer to Mirror Motor Circuit Malfunction.

Circuit/System Testing

Mirror Motor Circuit Malfunction

1. Ignition OFF, disconnect the harness connector X3 at the appropriate door switch.
2. Ignition ON, verify a test lamp does not illuminate between the following control circuit terminals and ground:

* Control circuit terminal 1
* Control circuit terminal 2
* Control circuit terminal 6

• If the test lamp illuminates, test the appropriate control circuit for a short to voltage.

3. Ignition OFF, test for infinite resistance between the following control circuits and ground:

* Control circuit terminal 1
* Control circuit terminal 2
* Control circuit terminal 6

• If less the specified value, test the appropriate control circuit for a short to ground.

4. Test for 40-100 ohms of resistance between the control circuit terminal 1 and the control circuit terminal 6.

• 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. Test for 40-100 ohms of resistance between the control circuit terminal 2 and the control circuit terminal 6.

• 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.

6. If all circuits test normal, replace the appropriate door switch.

Mirror Position Sensor Circuit Malfunction

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:

* 5-volt reference circuit terminal 7
* Signal circuit terminal 4
* Signal circuit terminal 5
* Low reference circuit terminal 10

• 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:

* 5-volt reference circuit terminal 7
* Signal circuit terminal 4
* Signal circuit terminal 5
* Low reference circuit terminal 10

• If less than the specified value, test the appropriate circuit for a short to ground.

4. Test for 4K-7K ohms of resistance between the 5-volt reference circuit terminal 7 and the low reference circuit terminal 10.

• If not within the specified range, test the 5-volt reference circuit and the low reference circuit for an open/high resistance. If the circuits test normal, test or replace the rearview mirror motor.

5. Test for 1K-7K ohms of resistance between the 5-volt reference circuit terminal 7 and the signal circuit terminal 4.

• If not within the specified range, test the signal circuit for an open/high resistance. If the circuits test normal, test or replace the rearview mirror motor.

6. Test for 1K-7K ohms of resistance between the 5-volt reference circuit terminal 7 and the signal circuit terminal 5.

• If not within the specified range, test the signal circuit for an open/high resistance. If the circuits test normal, test or replace the rearview mirror motor.

7. If all circuits test normal, replace the appropriate door switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Outside Rearview Mirror Motor Replacement
* Control Module References for DDS or PDS replacement, setup, and programming Programming and Relearning

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