Automatic transaxle system relies on various measurement data
to determine the current control status and extrapolate the necessary
compensation values. These values are used to control the actuators and
achieve the desired control output. If a problem with the drivetrain,
including the transaxle, has been identified, perform self-diagnosis and
basic transaxle inspection (oil and fluid inspection) and then check
the control system's components using the diagnosis tool.
| Control System Composition |
Fault Diagnosis
Features a fail-safe mechanism that provides "limp-home" 4th
gear hold to enable the vehicle to be driven to the owner's home or
dealer shop.
Fail-Safe: The TCM provides 4th gear hold and Reverse gear in the event of a malfunction.
Limp Home: Maintains minimal functionality (Drive(4th gear
hold), Reverse) in the event of a malfunction, making it possible for
the vehicle to reach the dealer shop.
Self-diagnosis
Transaxle Control Module(TCM) is in constant communication
with the control system's components (sensors and solenoids). If an
abnormal signal is received for longer than the predefined duration, TCM
recognizes a fault, stores the fault code in memory, and then sends out
a fault signal through the self-diagnosis terminal. Such fault codes
are independently backed up and will not be cleared even if the ignition
switch is turned off, the battery is disconnected, or the TCM connector
is disconnected.
| • |
Disconnecting a sensor or an actuator connector while the
ignition switch is in the "On" position generates a Diagnostic Trouble
Code (DTC) and commits the code to memory. In such event, disconnecting
the battery will not clear the fault diagnosis memory. The diagnosis
tool must be used to clear the fault diagnosis memory. |
| • |
Before removing or installing any part, read the diagnostic
trouble codes and then disconnect the battery negative (-) terminal. |
| • |
Before disconnecting the cable from battery terminal, turn
the ignition switch to OFF. Removal or connection of the battery cable
during engine operation or while the ignition switch is ON could cause
damage to the TCM. |
| • |
When checking the generator for the charging state, do not
disconnect the battery '+' terminal to prevent the Engine Control
Module(ECM) from damage due to the voltage. |
| • |
When charging the battery with the external charger, disconnect the vehicle side battery terminals to prevent damage to the TCM. |
|
Checking Procedure (Self-diagnosis)
| • |
When battery voltage is excessively low, diagnostic trouble
codes can not be read. Be sure to check the battery for voltage and the
charging system before starting the test.
|
|
Inspection Procedure (Using the GDS)
| 1. |
Turn OFF the ignition switch. |
| 2. |
Connect the GDS to the data link connector on the lower crash pad. |
| 3. |
Turn ON the ignition switch. |
| 4. |
Use the GDS to check the diagnostic trouble code. |
| 5. |
Repair the faulty part from the diagnosis chart. |
| 6. |
Erase the diagnostic trouble code. |
| • |
After replacing the automatic transaxle, use the GDS to reset
(erase the TCM learning values). Then perform Transaxle Control Module
(TCM) learning to provide optimum shift quality.
(Refer to Automatic Transaxle Control System - "Repair procedures") |
| • |
Adding automatic transaxle fluid.
(Refer to Hydraulic System - "Fluid") |
| • |
After servicing the automatic transaxle or TCM, clear the
Diagnostic Trouble Code (DTC) using the GDS tool. Diagnostic Trouble
Codes (DTC) cannot be cleared by disconnecting the battery. |
|
Adjustment
Transaxle Control Module(TCM) Learning
When shift shock is occurred or parts related with the transaxle are replaced, TCM learning should be performed.
In the following case, TCM ...
Hyundai Azera: Description and Operation
Fifth generation HG (2011–2024) / Hyundai Azera 2011-2024 Service Manual / Automatic Transaxle System / Automatic Transaxle Control System / Description and Operation
Repair procedures