GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2009 🢒 HHR 🢒 Seats 🢒 Power Seats 🢒 Power Seat Inoperative

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.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Seat Adjuster Switch B+

1, 2

1

--

--

Front Vertical Motor Down Control

1, 2

1

--

--

Front Vertical Motor Up Control

1, 2

1

--

--

Horizontal Motor Forward Control

1, 2

1

--

--

Horizontal Motor Rearward Control

1, 2

1

--

--

Rear Vertical Motor Down Control

1, 2

1

--

--

Rear Vertical Motor Up Control

1, 2

1

--

--

Seat Adjuster Switch Ground

--

1

--

--

1. Power seat inoperative

2. Lumbar support inoperative

Circuit/System Description

The power seat is controlled through the driver seat adjuster switch. Battery voltage is supplied at all times to the seat adjuster switch from the PWR SEAT 30 A circuit breaker that is located in the underhood fuse block. When the seat adjuster switches are in an inactive state, the switch contacts are closed to the switch ground circuit.

All seat motors are reversible. For example, when the seat horizontal forward switch is pressed to move the entire seat forward, battery voltage is applied through the switch contacts and the seat horizontal motor forward control circuit to the motor. The motor is grounded through the horizontal motor rearward switch contacts and the horizontal motor rearward control circuit to the motor. The motor runs in order to drive the entire seat forward until the switch is released. Moving the entire seat rearward works similarly to moving the entire seat forward, except that battery positive voltage and ground are applied on opposite circuits causing the motor to run in the opposite direction. All seat motors are powered this way.

Reference Information

Schematic Reference

Driver Seat Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Power Seats System Description and Operation

Electrical Information Reference

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

Circuit/System Verification

Operate the seat switches for the seat directional motors listed below in both directions. The seat should move in the commanded directions.

    • Horizontal Motor
    • Front Vertical Motor
    • Rear Vertical Motor
⇒If the power seat is inoperative in all directions, refer to the Seat Adjuster Switch Circuit Test.
⇒If one or more of the seat adjuster motors operate, refer to the Seat Adjuster Motor Circuit Test.

Circuit/System Testing

Seat Adjuster Switch Circuit Test

  1. Ignition OFF, disconnect the harness connector at the seat adjuster switch.
  2. Test for less than 5 Ω between the ground circuit terminal B and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify that a test lamp illuminates between the appropriate B+ circuit terminal D and ground.
    4. ⇒If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  4. If all circuits test normal, test or replace the seat adjuster switch.

Seat Adjuster Motor Circuit Test

  1. Ignition OFF, disconnect the harness connector at the appropriate seat adjuster motor.
  2. Connect a test lamp between control circuit terminal 1 and control circuit terminal 2.
  3. Ignition ON, command the appropriate seat motor Forward and Rearward or Up and Down using the seat adjuster switch. The test lamp should turn ON when commanding the forward and rearward or up and down states.
    4. ⇒If the test lamp remains OFF for either of the commands, test the control circuits for a short to ground or an open/high resistance. If the circuits test normal, test or replace the seat adjuster switch.
  4. If all circuits tests normal, test or replace the appropriate seat motor.

Component Testing

Driver Seat Adjuster Switch

  1. Ignition OFF, disconnect the harness connector at the driver seat adjuster switch.
  2. Test for infinite resistance between the B+ terminal D and the control terminals listed below with the switch in the open position.
    3. • Seat front vertical up terminal A
    • Seat front vertical down terminal H
    • Seat horizontal forward terminal C
    • Seat horizontal rearward terminal F
    • Seat rear vertical up terminal E
    • Seat rear vertical down terminal G
    ⇒If not the specified value, replace the seat adjuster switch.
  3. Test for less than 2 Ω between the B+ terminal D and the control terminals listed below with the appropriate switch in the closed position.
    4. • Seat front vertical up terminal A
    • Seat front vertical down terminal H
    • Seat horizontal forward terminal C
    • Seat horizontal rearward terminal F
    • Seat rear vertical up terminal E
    • Seat rear vertical down terminal G
    ⇒If greater than the specified range, replace the seat adjuster switch.
  4. Test for less than 2 Ω between the ground terminal B and the control terminals listed below with the switch in the open position.
    5. • Seat front vertical up terminal A
    • Seat front vertical down terminal H
    • Seat horizontal forward terminal C
    • Seat horizontal rearward terminal F
    • Seat rear vertical up terminal E
    • Seat rear vertical down terminal G
    ⇒If greater than the specified range, replace the seat adjuster switch.

Seat Motor

  1. Ignition OFF, disconnect the harness connector at the appropriate seat motor.

    2. Important: When performing the following tests, make sure that the seat is not already in the position the test is attempting to produce.

  2. Install a 30 A fused jumper wire between the control terminal 1 and 12 V. Momentarily install a jumper wire between the control terminal 2 and ground. The seat motor should momentarily perform the FORWARD/DOWN function.
    3. ⇒If the function does not perform as specified, replace the seat motor.
  3. Reverse the polarity of jumper wires; the a seat motor should perform the REARWARD/UP function.
    4. ⇒If the function does not perform as specified, replace the seat motor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Power Seat Switch Replacement