GM Service Manual Online
For 1990-2009 cars only

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

  1. When diagnosing a memory seat system or a Sit-N-Lift mobility seat system condition, perform the Diagnostic System Check - Vehicle in Vehicle DTC Information before using the symptom tables in order to verify that all of the following are true:
  2. • There are no DTCs set.
    • The control modules can communicate via the serial data link.
  3. Refer to the system description and operation from the following list in order to familiarize yourself with the system functions:
  4. •  Power Seats System Description and Operation
    •  Heated Seats Description and Operation
    •  Memory Seats Description and Operation
    •  Sit-N-Lift Mobility Seat Description and Operation

Visual/Physical Inspection

    • Inspect for aftermarket devices which could affect the operation of the power seat systems. Refer to Checking Aftermarket Accessories in Wiring Systems.
    • Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
    • Inspect the seat adjuster track for conditions which may cause binding or objects within the seat adjustment range which may obstruct movement or interfere with wiring.

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

Symptom List

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

    •  Power Seat Inoperative
    •  Memory Seat Feature Inoperative
    •  Sit-N-Lift Mobility Seat Inoperative
    •  Sit-N-Lift Mobility Seat Does Not Enter Diagnostic Mode
    •  Heated Seat Always On
    •  Heated Seat Inoperative