Kia Optima: Automatic Transaxle Control System / Transaxle Control Module (TCM)
Description and operation
The module receives and processes signals from various sensors and implements
a wide range of transaxle controls to ensure optimal driving conditions for the
driver.
Functions
| • |
Monitors the vehicle's operating conditions to determine the optimal
gear setting.
|
| • |
Performs a gear change if the current gear setting differs from the identified
optimal gear setting.
|
| • |
Determines the need for torque converter clutch activation and engages
the clutch accordingly.
|
| • |
Calculates the optimal line pressure level by constantly monitoring the
torque level and adjusts the pressure accordingly.
|
| • |
Diagnoses the faults and failures for automatic transaxle.
|
Repair procedures
| 1. |
The automatic transaxle system can be more quickly diagnosed for troubles
by using the vehicle diagnostic system (KDS).
KDS provides the following information.
| (1) |
Self diagnosis : Inspects and displays diagnostic trouble code
(DTC)
|
| (2) |
Sensor data : Checks the system input/output value status
|
| (3) |
Forced operation : Checks the system operating status
|
| (4) |
Additional function : Controls system options, zero point adjustment
and other functions
|
|
| 1. |
TCM ground circuit test : Measure the resistance between TCM and chassis
ground. (Inspect the terminal connected to the chassis ground with the back
of harness connector as the inspection point of TCM side.)
|
| 2. |
TCM connector test : Disconnect the TCM connector and visually check
the ground terminals on TCM side and harness side for bent pins or poor
contact pressure.
|
| 3. |
If problem is not found in Steps 1 and 2, the TCM could be faulty.
If so, replace the TCM with a new one, and then check the vehicle again.
If the vehicle operates normally then the problem was likely with the TCM.
|
| 4. |
Reinspection of original TCM : Install the original TCM (probably broken)
into a known-good vehicle and check the vehicle. If the problem occurs again,
replace the original TCM with a new one.
If the problem does not reoccur, this is an intermittent problem and
other part may be faulty.
|
| 1. |
Remove the TCM.
(Refer to Engine Control / Fuel System - "Engine Control Module")
|
| 1. |
Install the TCM.
(Refer to Engine Control / Fuel System - "Engine Control Module")
|
Description and operation
Description
Automatic transaxle control system relies on various measurements to determine
the current control status and determine the necessary compensation ...
Specifications
Specification
Item
Specification
Type
*NTC thermistor
Temp.[(°C)°F] / Resistance (kΩ)
...
Other information:
Description and operation
Description
The auto defogging sensor is installed on the front window glass. The sensor
judges and sends signal if moisture occurs to blow out wind for defogging. The air
conditioner control module receives signal from the sensor and restrains moisture
...
Fuel pressure test
Fuel Pressure Test
1.
Release the residual pressure in fuel line.
(Refer to Fuel Delivery System - "Release Residual Pressure in Fuel Line")
...
Automatic Transaxle Control System
Transaxle Oil Temperature Sensor (Main Harness)