GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2005 🢒 Rendezvous - AWD 🢒 Accessories 🢒 Navigation Systems 🢒 DTC B1600, B1605, B1630, or B1635

Circuit Description

The memory seat module (MSM) monitors the outputs to the mirror motors during mirror operation. During normal operation, the mirror motors are checked against out-of-range limits. If the MSM sees the mirror motor output range high, a DTC B1600, B1605, B1630, or B1635 is set and the mirror motor output and the memory recall is disabled for the motor affected.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC B1600 Driver Mirror Motor Vertical Circuit
    • DTC B1605 Driver Mirror Motor Horizontal Circuit
    • DTC B1630 Right Front Mirror Motor Vertical Circuit
    • DTC B1635 Right Front Mirror Motor Horizontal Circuit

Conditions for Running the DTC

Battery input voltage between 9-16 volts

Conditions for Setting the DTC
    • The outside rearview mirror motor circuit short to voltage
    • The outside rearview mirror motor circuit short to ground

Action Taken When the DTC Sets

The MSM will disable the affected motor output.

Conditions for Clearing the DTC
    • The MSM no longer detects the mirror motor circuit short to voltage.
    • The MSM no longer detects the mirror motor circuit short to ground.
    • DTC will clear after 50 consecutive ignition cycles.

Diagnostic Aids

If the DTC does not reset after it has been cleared, then the malfunction may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Listen for the motor operation. Command both the Up and Down or Right and Left states. Repeat the commands, as necessary.

    2.

  2. This step verifies that the MSM is providing output to the mirror motor.

    3.

  3. This step verifies that the MSM is providing output to the mirror assembly.

    4.

  4. This step tests the mirror motor control circuits for a short to voltage or ground.

Step

Action

Yes

No

Schematic Reference: Outside Rearview Mirror Schematics

Connector End View Reference: Power Door Systems Connector End Views or Power Seat Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, command the appropriate mirror motor Up and Down or Right and Left.

Does the mirror motor turn Up and Down or Right and Left with each command?

Go to Diagnostic Aids

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the appropriate mirror motor.
  3. Connect a test lamp between the appropriate mirror motor control circuits.
  4. Turn ON the ignition, with the engine OFF.
  5. With a scan tool, command the appropriate mirror motor Up and Down or Right and Left.

Does the test lamp illuminate?

Go to Step 6

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Connect the appropriate mirror motor.
  3. Disconnect the appropriate mirror motor assembly.
  4. Connect a test lamp between the appropriate mirror motor assembly control circuits.
  5. Turn ON the ignition, with the engine OFF.
  6. With a scan tool, command the appropriate mirror motor Up and Down or Right and Left.

Does the test lamp illuminate?

Go to Step 7

Go to Step 5

5

Test the appropriate mirror motor control circuit of the appropriate mirror motor for a short to voltage or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 12

Go to Step 8

6

Inspect for poor connections at the harness connector of the outside rearview mirror motor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 12

Go to Step 9

7

Inspect for poor connections at the harness connector of the outside rearview mirror assembly. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 12

Go to Step 10

8

Inspect for poor connections at the harness connector of the memory seat module (MSM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 12

Go to Step 11

9

Replace the outside rearview mirror motor. Refer to Outside Rearview Mirror Motor Replacement .

Did you complete the replacement?

Go to Step 12

--

10

Replace the outside rearview mirror assembly. Refer to Power Mirror Replacement .

Did you complete the replacement?

Go to Step 12

--

11

Replace the MSM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 12

--

12
  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