Specifications

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Testing Testing Transmission Systems
4.2.3 Important Tips for Testing Transmission Systems
• Make sure that you identify the SMG transmission to the scan tool as an automatic to obtain
codes and data.
• Some transmissions may have different controllers that can be EGS or AGS.
• On OBD-II (1996 and later) vehicles, the transmission MIL may turn on simultaneously with
the engine MIL for any emission-related DTC.
• Engine pending codes may turn on the transmission MIL.
• With the transmission MIL on, the transmission will be in limp home mode (4th or 5th gear).
• With a DTC set, the transmission MIL is either a gear sign with an exclamation mark in the
middle, or the instrument panel illuminates with “Trans Program”, depending on the
instrument cluster type.
• Disconnecting the battery will not erase transmission or engine codes (late model OBD-II
vehicles) but may turn the transmission MIL off. On OBD-I vehicles (1988–95), codes clear
and adaptations usually reset with the vehicle battery disconnected.
IMPORTANT:
Do not leave the key on when disconnecting or connecting the vehicle battery or module failure
may result.
4.2.4 Functional Tests
Functional Tests allow you to activate and test components of the transmission electronic control
system. Selecting Functional Tests from the Main Menu displays a list of tests, that varies
depending on the vehicle and system identified.
Actuator Tests
Selecting Actuator Tests displays a list of tests. As each actuator test is selected, the actuators
pulse On/Off for a predetermined period of time.
Available actuator tests may vary from the list below, depending on the transmission:
• Solenoid Valve 1
• Solenoid Valve 2
• Solenoid Valve 3
• Pressure Regulator 1
• Pressure Regulator 2
• Pressure Regulator 3
• Pressure Regulator 4
• Shift Lock Solenoid Valve