Chevrolet Trax: Symptoms - power seats

NOTE: The following steps must be completed before using the symptom tables.

1. Perform the Diagnostic System Check - Vehicle before using the Symptom Tables in order to verify that all of the following are true:

• There are no DTCs set.
• The control modules can communicate via the serial data link.

2. Review the system operation in order to familiarize yourself with the system functions. Refer to the following system descriptions:

• Lumbar Support Description and Operation
• Memory Seats Description and Operation
• Power Seats System Description and Operation

Visual/Physical Inspection

• Inspect for aftermarket devices which could affect the operation of the system. Refer to Checking Aftermarket Accessories .
• Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections .

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

• Lumbar Support Malfunction
• Memory Seat Feature Malfunction
• Power Seat Malfunction (Without Memory A45), Power Seat Malfunction (With Memory A45)

LUMBAR SUPPORT MALFUNCTION

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/System Description

The seat lumbar support is controlled through the seat lumbar support switch. Battery voltage is supplied at all times to the lumbar switch through a 15 A fuse located in the rear body fuse block. When the lumbar switch is in an inactive state, the switch contacts are closed to the switch ground circuit.

The lumbar motor is reversible. For example, when the lumbar forward switch is pressed to move the lumbar support forward, battery voltage is applied through the switch contacts and the lumbar motor forward control circuit to the motor. The motor is grounded through the lumbar motor rearward switch contacts and the lumbar motor rearward control circuit to the motor. The motor runs in order to drive the lumbar support forward toward the occupants back until the switch is released. Moving the lumbar support rearward works similarly to moving the lumbar support forward, except that battery positive voltage and ground are applied on opposite circuits causing the motor to run in the opposite direction.

Reference Information

Schematic Reference

• Driver Seat Schematics (Encore), Driver Seat Schematics (Trax)
• Passenger Seat Schematics (Encore)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Description and Operation

Lumbar Support Description and Operation

Electrical Information Reference

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

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the appropriate S65 Seat Lumbar Support Switch. It may take up to 2 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal H and ground.

If 10 ohms or greater

1. Test for less than 2 ohms in the ground circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, repair the open/high resistance in the ground connection.

If less than 10 ohms

3. Ignition ON.
4. Verify a test lamp illuminates between the B+ circuit terminal E and ground.

If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF.
2. Test for less than 2 ohms in the B+ circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse.

If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF.
2. Test for infinite resistance between the B+ circuit and ground.

• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance

3. Test for greater than 10 ohms between each control circuit listed below and ground:

• Lumbar forward control circuit terminal A
• Lumbar rearward control circuit terminal D

If 10 ohms or less, disconnect the harness connector at the M53 Seat Lumbar Support Motor and retest to verify if the short is in the circuit or the component.

If greater than 10 ohms, test or replace the S65 Seat Lumbar Support Switch.

If the test lamp illuminates

5. Ignition OFF, connect the harness connector at the S65 Seat Lumbar Support Switch and disconnect the harness connector at the M53 Seat Lumbar Support Motor.
6. Connect a test lamp between control circuit terminal A and control circuit terminal B, ignition ON.
7. Verify the test lamp turns ON when commanding the lumbar support Forward and Rearward using the S65 Seat Lumbar Support Switch.

If the test lamp remains OFF during either of the commands

1. Ignition OFF, disconnect the harness connector at the S65 Seat Lumbar Support Switch.
2. Test for infinite resistance between each control circuit and ground.

• If less than Infinite resistance, repair the short to ground on the circuit.
• If infinite resistance

3. Test for less than 2 ohms in each control circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the S65 Seat Lumbar Support Switch.

If the test lamp remains ON during either of the commands

1. Ignition OFF, disconnect the harness connector at the S65 Seat Lumbar Support Switch, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.

• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the S65 Seat Lumbar Support Switch.

If the test lamp turns ON during each of the commands

8. Test or replace the M53 Seat Lumbar Support Motor.

Component Testing

Lumbar Support Switch

1. Ignition OFF, disconnect the harness connector at the appropriate S65 Seat Lumbar Support Switch.
2. Test for infinite resistance between the B+ terminal E and each control terminal with the switch in the open position.

If less than infinite resistance

Replace the S65 Seat Lumbar Support Switch.

If infinite resistance

3. Test for less than 2 ohms between the B+ terminal E and each control terminal with the appropriate switch in the closed position.

If 2 ohms or greater

Replace the S65 Seat Lumbar Support Switch.

If less than 2 ohms

4. Test for less than 2 ohms between the ground terminal H and each control terminal with the switch in the open position.

If 2 ohms or greater

Replace the S65 Seat Lumbar Support Switch.

If less than 2 ohms

5. All OK.

Seat Lumbar Support Motor

1. Ignition OFF, disconnect the harness connector at the M53 Seat Lumbar Support Motor.

NOTE: When performing the following tests, make sure that the lumbar support is not already in the position the test is attempting to produce.

2. Install a 30 A fused jumper wire between control terminal A 12 V.
3. Momentarily install a jumper wire between control terminal B and ground. The M53 Seat Lumbar Support Motor should momentarily perform the lumbar FORWARD function.

If the motor does not perform the lumbar FORWARD function

Replace the M53 Seat Lumbar Support Motor

If the motor performs the lumbar FORWARD function

4. Reverse the polarity of jumper wires; the lumbar motor should perform REARWARD function.

If the motor does not perform the lumbar REARWARD function

Replace the M53 Seat Lumbar Support Motor.

If the motor performs the lumbar REARWARD function

5. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Driver or Passenger Seat Lumbar Control Switch Replacement
• Driver or Passenger Seat Back Cushion Frame Replacement

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