Kia Optima Hybrid Owner's Manual Quiz
Automatic Transmission

Transmission Control Module (TCM) Repair Procedures

In this manual: Automatic Transmission
General Information — 4Engine Mechanical System — 50Engine Electrical System — 20Emission Control System — 30Engine Control System/Fuel System — 84Automatic Transmission — 98Drive Shaft and Axle — 15Suspension System — 36Steering — 12Restraints — 50Brake System — 38Body (Interior and Exterior) — 54Body Electrical System — 233Heating, Ventilation, and Air Conditioning — 57
12steps
~72min
3/5difficulty
010203040509.87N·mlb·ft
Tightening torque found on this page
Done 0 of 12

Inspection

TCM Troubleshooting Procedure

  1. TCM GROUND CIRCUIT INSPECTION: Measure the resistance between the TCM and chassis ground using the rear side of the TCM harness connector as the TCM side test point. If a problem is found, repair it.

    Specification: Below 1 Ω

  2. Inspect the TCM connector: Disconnect the TCM connector and visually inspect the ground terminals on the TCM side and the harness side for bent pins or poor contact tension. If a problem is found, repair it.
  3. If no problem is found in steps 1 and 2, the TCM may be faulty. If so, before replacing the TCM, make sure there are no DTCs, then replace the TCM with a new one and recheck the vehicle. If DTCs were detected, check them first before replacing the TCM.
  4. Retest the original TCM: Install the original TCM (may be faulty) into a known good vehicle and inspect the vehicle. If the problem recurs, replace the original TCM with a new one. If the problem does not occur, the problem is intermittent.

Removal
  • Be sure to read and observe the "General Safety Information and Caution" before performing any work on the high voltage system. Failure to follow the safety instructions may result in serious electrical injury.
  • Always disconnect the high-voltage circuit in accordance with the "High Voltage Disconnection Procedure" before performing any work on the high-voltage system to avoid serious electric shock.
  1. Disconnect the negative (-) battery cable from the 12V battery.
  2. Remove the air duct (A).

    Tightening torque: 7.8 ~ 9.8 N·m

  3. Remove the air cleaner assembly.
    1. Disconnect the breather hose (A).
    2. Disconnect the air intake hose (B) and remove the air cleaner assembly (C).
    Tightening torque: Hose clamp bolt: 2.9 ~ 4.9 N·m Air cleaner mounting bolts: 7.8 ~ 9.8 N·m
    • When installing the air intake hose, align the clamp plate with the hose stopper.
    • When installing the air intake hose, align the center of the mark on the hose with the rib of the throttle body.
  4. Disconnect the TCM connector (A) and remove the cover of the passenger compartment relay block (B).
  5. Remove the resolver mounting bolt (A) and the drain tube fixing bolt (B), then position the HPCU.

    Tightening torque: 3.9 ~ 5.9 N·m

  6. Disconnect the (+) battery cable (A) after loosening the nut.
  7. Move the (+) battery cable (A) aside and remove the TCM bracket mounting bolt (B).

    Tightening torque: 9.8 ~ 11.8 N·m

  8. Remove the TCM (A) by removing the TCM bracket mounting nut.

    Tightening torque: 9.8 ~ 11.8 N·m

Installation

  1. Install in the reverse order of removal.
    • Perform the procedure to store the TCM adaptive values. (Refer to "Automatic Transmission Control System - Repair Procedures")
    • After replacing the TCM, perform the procedures related to the ECM. (Refer to Engine Control/Fuel System - Engine Control Module)

Test yourself

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