GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 2001 🢒 Silhouette Ext. 🢒 Body and Accessories 🢒 Seats 🢒 DTC B1770, B1775, B1780, B1785, B1790, B1805, or B2415

Circuit Description

The seat adjuster motors are controlled by the memory seat module through the adjuster motor supply circuits. The memory seat module also monitors current flow through the adjuster motor supply circuits. In an active state the adjuster motor supply circuits are switched to power and ground within the memory seat module. The direction of the adjuster motor rotation is determined by which of the supply circuits is switched to battery positive voltage and which is grounded.

Conditions for Setting the DTC

The adjuster motor supply circuit current monitored by the memory seat module is high, low, or open.

Action Taken When the DTC Sets
    • The memory seat module will disable the seat adjuster motor for which a current status DTC is set.
    • When the fault is no longer present a history status DTC will be stored, and adjuster motor operation will be restored.

Conditions for Clearing the DTC
    • The DTC will be current for as long as the fault is present.
    • When the fault is no longer present the DTC will be a history status code.
    • The history DTC will be cleared after 100 error free ignition cycles, or by using the scan tool clearing DTCs feature.

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. Verify that the DTC is current or history by attempting to operate the seat adjuster motor for which the code is set.

    2.

  2. Tests the adjuster motor supply circuits for proper operation.

Step

Action

Yes

No

Schematic Reference: Memory Seats Schematics

1

Did you perform the Power Seat Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Power Seat Systems

2

  1. Install a scan tool.
  2. With a scan tool, operate the seat adjuster motor through the full range of adjustment in both directions.

Does the seat adjuster motor operate through the full range of adjustment?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

  1. Disconnect the seat adjuster motor connector.
  2. Connect a test lamp across the adjuster motor supply circuits.
  3. With a scan tool, command the adjuster motor active in both directions.

Does the test lamp turn ON and OFF with each command?

Go to Step 5

Go to Step 4

4

Test and repair the adjuster motor supply circuits for the following conditions:

    • Short to ground
    • Open or high resistance
    • Short to voltage

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 6

5

Inspect for poor connections at the adjuster motor connector. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 7

6

Inspect for poor connections at the harness connector of the memory seat module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

7

Replace the adjuster motor assembly. Refer to Power Seat Adjuster Mechanism Replacement .

Did you complete the replacement?

Go to Step 9

--

8

Replace the memory seat module.

Did you complete the replacement?

Go to Step 9

--

9
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the system in order to verify the repair.

Does the DTC reset?

Go to Step 2

System OK