GM Service Manual Online
For 1990-2009 cars only

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.

DTC Descriptors

DTC B1580 00: Mirror Horizontal Position Sensor Circuit

DTC B1590 00: Mirror Vertical Position Sensor Circuit

Diagnostic Fault Information

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

1

B1580

--

Driver/Passenger Mirror Vertical Position Sensor Signal

B1590

1

B1590

--

Low Reference

B1580, B1590

B1580, B1590

B1580, B1590

--

1. Memory Mirror Malfunction

Circuit/System Description

The driver door module (DDM) and passenger door module (PDM) receive mirror position signals from the mirror horizontal and vertical position sensors. These signals are used by the door modules for memory recall functions of the driver and passenger mirrors. The door modules command the mirror memory settings based upon the voltage level received back from the position sensors. Each door module provides a 5-volt supply, a signal, and ground circuit for each of the position sensors. The horizontal and vertical position sensors are variable resistors that the door modules monitor voltage levels across. When a memory setting is recalled, the door modules command the mirror motors in the appropriate directions until the stored position sensor voltage levels are achieved. The DDM and PDM monitor the signal circuits to determine if the voltage level is out of range.

Conditions for Running the DTC

Battery voltage must be between 9-16 volts.

Conditions for Setting the DTC

B1580

An improper voltage level is seen on the horizontal position sensor signal circuit.

B1590

An improper voltage level is seen the vertical position sensor signal circuit.

Actions Taken When the DTC Sets

Memory mirror recall functions are suspended as long as the fault is present.

Conditions for Clearing the DTC

    • A current DTC will clear when the fault is no longer present.
    • A history DTC will clear after 40 fault free ignition cycles.

Reference Information

Schematic Reference

Outside Rearview Mirror Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Outside Mirror Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information.

Circuit/System Verification

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

Circuit/System Testing

Driver

  1. Ignition OFF, disconnect the X2 harness connector at the outside rearview mirror.
  2. Wait 1 minute, test for less than 20.0 ohms between the low reference circuit terminal 12 and ground.
  3. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the DDM.
  4. Ignition ON, test for 4.8 - 5.2 volts between the 5-volt reference circuit terminal 9 and ground.
  5. If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the DDM.
    If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the DDM.
  6. Install a 3-A fused jumper wire between the signal circuit terminal 11 and the 5-volt reference circuit terminal 9. Verify the scan tool Mirror Horizontal Position parameter is greater than 4.8 volts.
  7. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the DDM.
  8. Install a 3-A fused jumper wire between the signal circuit terminal 10 and the 5-volt reference circuit terminal 9. Verify the scan tool Mirror Vertical Position parameter is greater than 4.8 volts.
  9. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the DDM.
  10. Install a 3-A fused jumper wire between the signal circuit terminal 11 and the low reference circuit terminal 12. Verify the scan tool Mirror Horizontal Position parameter is less than 0.5 volt.
  11. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the DDM.
  12. Install a 3-A fused jumper wire between the signal circuit terminal 10 and the low reference circuit terminal 12. Verify the scan tool Mirror Vertical Position parameter is less than 0.5 volt.
  13. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the DDM.
  14. If all circuits test normal, test or replace the outside rearview mirror.

Passenger

  1. Ignition OFF, disconnect the harness connector at the outside rearview mirror.
  2. Wait 1 minute, test for less than 20.0 ohms between the low reference circuit terminal 9 and ground.
  3. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the PDM.
  4. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 12 and ground.
  5. If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the PDM.
    If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the PDM.
  6. Install a 3-A fused jumper wire between the signal circuit terminal 11 and the 5-volt reference circuit terminal 9. Verify the scan tool Mirror Horizontal Position parameter is greater than 4.8 volts.
  7. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the PDM.
  8. Install a 3-A fused jumper wire between the signal circuit terminal 10 and the 5-volt reference circuit terminal 9. Verify the scan tool Mirror Vertical Position parameter is greater than 4.8 volts.
  9. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the PDM.
  10. Install a 3-A fused jumper wire between the signal circuit terminal 11 and the low reference circuit terminal 9. Verify the scan tool Mirror Horizontal Position parameter is less than 0.5 volt.
  11. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the PDM.
  12. Install a 3-A fused jumper wire between the signal circuit terminal 10 and the low reference circuit terminal 9. Verify the scan tool Mirror Vertical Position parameter is less than 0.5 volt.
  13. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the PDM.
  14. If all circuits test normal, test or replace the outside rearview mirror.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Power Mirror Replacement
    •  Control Module References for DDM or PDM replacement, setup, and programming