GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The horizontal and vertical mirror position sensors are potentiometers powered by the door modules. Both the driver door module (DDM) and passenger front door module (PDM) determine the horizontal and vertical positions of their respective mirror based on the signal voltages received from the mirror position sensors. For more detailed information concerning power mirror operation refer to Outside Mirror Description and Operation .

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC B1580 Mirror Horizontal Position Sensor Circuit
    • DTC B1590 Mirror Vertical Position Sensor Circuit

This vehicle has DTCs which include DTC symptoms. For more information on DTC symptoms, refer to DTC Symptom Description .

DTC Symptom

DTC Symptom Descriptor

08

Sensor Out of Range/Open

Conditions for Running the DTC

    • The DDM and the PDM must be powered.
    • DTC B1325 Battery Voltage Out of Range, must not be current.

Conditions for Setting the DTC

These DTCs will set if:

    • A mirror position sensor signal voltage is below 0.25 volt for 2 seconds.
    • A mirror position sensor signal voltage is above 4.75 volts for 2 seconds.

Action Taken When the DTC Sets

    • The door module will ignore the failed position sensor.
    • The door module will ignore memory set or recall for the mirrors.
    • Manual mirror adjustments will be allowed.

Conditions for Clearing the DTC

    • The condition responsible for setting the DTC no longer exists.
    • You issue a scan tool CLEAR DTCs command.
    • After 40 consecutive warm-up cycles without failure, the history DTC will be cleared.

Diagnostic Aids

If the Personalization Option is activated on a vehicle that does not have Memory Mirrors, DTCs B1580 and B1590 will set in error. If these DTCs are set on a vehicle that does not have the Memory Mirrors option, refer to Instrument Panel Module Programming and Setup to deactivate the option.

Thoroughly inspect the wiring and connectors. An incomplete inspection of the wiring and connectors may result in misdiagnosis causing part replacement with the reappearance of the malfunction. If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections .

Step

Action

Value(s)

Yes

No

Schematic Reference: Outside Rearview Mirror Schematics

Connector End View Reference: Vehicle Access Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Using the mirror position switch, move the applicable mirror to the limits of travel.
  4. With the scan tool, observe the applicable Mirror Horizontal and Vertical Position Sensor parameters in the associated door control module data list.

Does the scan tool indicate the voltage changes and is within the specified range?

0.25-4.75 V

Go to Step 9

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the C3 harness connector from the door module associated with the inoperative mirror.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the position sensor 5-volt reference circuit at the door control module pin.

Does the voltage measure near the specified value?

4.75-5.50 V

Go to Step 4

Go to Step 7

4

  1. Turn OFF the ignition.
  2. Connect a 3-amp fused jumper between the applicable mirror position sensor signal circuit and the mirror sensor low reference circuit at the door module pins.
  3. Turn ON the ignition, with the engine OFF.
  4. With the scan tool, observe the applicable mirror position parameter.

Does the scan tool indicate the voltage is near the specified value?

0-0.25 V

Go to Step 5

Go to Step 7

5

Inspect for poor connections at the C3 harness connector of the door module associated with the inoperative mirror. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 9

Go to Step 6

6

Replace the appropriate mirror. Refer to Outside Rearview Mirror Glass Replacement .

Did you complete the replacement?

--

Go to Step 9

--

7

Inspect for poor connections at the C 3 harness connector of the door control module associated with the inoperative mirror. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 9

Go to Step 8

8

Replace the appropriate door control module. Refer to Control Module References for replacement, setup and programming.

Did you complete the replacement?

--

Go to Step 9

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9

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

--

Go to Step  2

System OK