Hyundai Tucson: Automatic Transaxle System / Troubleshooting

- Troubleshooting Fault Diagnosis

• Features a fail-safe mechanism that provides "limp-home" 5th gear hold to enable the vehicle to be driven to the owner's home or dealer shop.

   

• Fail-Safe : The TCM provides 5th gear hold and Reverse gear in the event of a malfunction.

• Limp Home : Maintains minimal functionality (Drive (5th gear hold), Reverse) in the event of a malfunction, making it possible for the vehicle to reach the dealer shop.

Troubleshooting

Trouble symptom	Suspect area	Remedy
Shift delay	Damaged clutch / brake	Replace the brake or clutch.
	Faulty hydraulic control	Inspect the solenoid valve.
	Faulty hydraulic supply	Check the fluid level.
	Not performed TCM learning	TCM learning is required.
Vibration of the vehicle when shifting	Damaged clutch / brake	Replace the brake or clutch.
	Not performed TCM learning	TCM learning is required.
	Faulty hydraulic control	Inspect the solenoid valve.
	Faulty hydraulic supply	Check the fluid level.
Fixed gear (shift impossible)	Faulty hydraulic control	Inspect the solenoid valve.
		Replace the solenoid valve or valve body.
	Faulty harness & connector connection	Check the harness & connector of transaxle.
	Faulty TCM, SCU	Replace the TCM, SCU.
	Faulty CAN Communication	Inspect the CAN communication line.
	Faulty position sensor	Inspect the position sensor.
Limited gear (shift possible)	Faulty input & output speed sensor	Inspect the input & output speed sensor.
	Faulty harness & connector connection	Check the harness & connector of transaxle.
Poor acceleration	Faulty hydraulic control	Inspect the solenoid valve.
	Faulty hydraulic supply	Check the fluid level.
	Faulty oil pump	Replace the oil pump.

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 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 Transaxle Control Module (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.

• 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 diagnostic tool)

1.Turn OFF the ignition switch.

2.Connect the diagnostic tool to the data link connector on the lower crash pad.

3.Turn ON the ignition switch.

4.Use the diagnostic tool to check the diagnostic trouble code.

5.Repair the faulty part from the diagnosis chart.

6.Erase the diagnostic trouble code.

7.Disconnect the diagnostic tool.