GM Service Manual Online
For 1990-2009 cars only

Reading Diagnostic Trouble Codes DTC(s) With a Scan Tool

The recommended method for reading DTC(s) stored in the seat adjuster memory module memory is by using a scan tool plugged into the DLC connector (located under the instrument panel on the right side). Follow the scan tool instructions supplied by the tool manufacturer. The DTC(s) will be stored in the memory of the seat adjuster memory module as a Current or a History DTC.

Current Codes

The seat adjuster memory module will set the code as a current DTC under the following conditions:

    • The seat adjuster memory module determines that the test conditions and failure conditions for a particular DTC are true.
    • A current ignition cycle occurs.

All DTC(s) remain current until the following conditions exist:

    • The next fault-free ignition cycle occurs.
    • The seat adjuster memory module determines that the test conditions are true.
    • The seat adjuster memory module determines that the failure conditions are false.

The Current code then will become a History code only when the above conditions exist.

History Codes

When a DTC reports a failure and the failure was not in the current ignition cycle, the DTC will be stored as a history code. The seat adjuster memory module performs internal diagnostic tests in order to acknowledge that the related systems have reported a pass or fail condition. Each diagnostic test that fails is recorded in the seat adjuster memory module memory. The memory of the seat adjuster memory module may be accessed with a scan tool in order to determine which DTC circuit was at fault. A history DTC may be cleared (for any diagnostic test) by performing any of the following procedures:

    • Complete 100 subsequent ignition cycles with no diagnostic test reporting a fail.
    • Use a scan tool.

       Important: Disconnecting the battery or seat adjuster memory module connector will clear all current and history seat adjuster memory module DTC(s).

    • Disconnect the battery.
    • Disconnect the seat adjuster memory module connector.

After Diagnosis is Complete

After diagnosing a problem, in addition to repairing the discovered malfunction, clear any DTC(s) set and verify proper operation. In order to verify proper operation, you must duplicate the conditions when the customer's complaint occurred. If a DTC was set, you must duplicate the test conditions for that DTC (listed on the Diagnostic Trouble Code table). The DTC should not re-set after the repair has been completed.