TIBURON(GK) >2008 > G 2.7 DOHC > Automatic Transaxle System > Automatic Transaxle System>Troubleshooting (F4A42-2)  
INSPECTION PROCESS FOR TROUBLE SYMPTOMS
INSPECTION PROCEDURE 1
Communication with the scan tool
Possible cause
If communication with the scan tool is not possible, the cause may be a defective diagnostic trouble line or the TCM is not functioning.
Malfunction of diagnostic trouble line
Malfunction of connector
Malfunction of the TCM

INSPECTION PROCEDURE 2
Starting impossible
Possible cause
Starting is not possible when the selector lever is in P or N range. In such cases, the cause may be a defective engine system, torque converter or oil pump.
Malfunction of the engine system
Malfunction of the torque converter
Malfunction of the oil pump

INSPECTION PROCEDURE 3
Does not move
Possible cause
If the vehicle does not move forward when the selector lever is shifted from N to D range while the engine is idling, the cause may be abnormal line pressure or a malfunction of the underdrive clutch or valve body.
Abnormal line pressure
Malfunction of the underdrive solenoid valve
Malfunction of the underdrive clutch
Malfunction of the valve body

INSPECTION PROCEDURE 4
Does not reverse
Possible cause
If the vehicle does not reverse when the selector lever is shifted from N to R range while the engine is idling, the cause may be abnormal pressure in the reverse clutch or low and reverse brake or a malfunction of the reverse clutch, low and reverse brake or valve body.
Abnormal reverse clutch pressure
Abnormal low and reverse brake pressure
Malfunction of the low and reverse solenoid valve
Malfunction of the reverse clutch
Malfunction of the low and reverse brake
Malfunction of the valve body

INSPECTION PROCEDURE 5
Does not move (forward or reverse)
Possible cause
If the vehicle does not move forward or reverse when the selector lever is shifted to any position while the engine is idling, the cause may be abnormal line pressure, or a malfunction of the power train, oil pump or valve body.
Abonormal line pressure
Malfunction of the underdrive solenoid valve
Malfunction of the underdrive clutch
Malfunction of the valve body

INSPECTION PROCEDURE 6
Engine stalling when shifting
Possible cause
If the engine stalls when the selector lever is shifted from N to D or R range while the engine is idling, the cause may be a malfunction of the engine system, torque converter clutch soledoid, valve body or torque converter (torque converter clutch malfunction).
Malfunction of the engine system
Malfunction of the torque converter clutch solenoid
Malfunction of the valve body
Malfunction of the torque converter (Malfunction of the torque converter clutch)

INSPECTION PROCEDURE 7
Shocks when changing from N to D and range time lag
Possible cause
If abnormal shocks or a time lag of 2 second or more occurs when the selector lever is shifted from N to D range while the engine is idling, the cause may be abnormal underdrive clutch pressure or a malfunction of the underdrive clutch, valve body or closed throttle position switch.
Abnormal line pressure
Malfunction of the underdrive solenoid valve
Malfunction of the underdrive clutch
Malfunction of the valve body
Malfunction of the closed throttle position switch

INSPECTION PROCEDURE 8
Shock when changing from N to R and large time lag
Possible cause
If abnormal shocks or a time lag of 2 seconds or more occurs when the selector lever is shifted from N to R range while the engine is idling, the cause may be abnormal reverse clutch pressure or low and reverse brake pressure, or a malfunction or the reverse clutch, low and reverse brake, valve body.
Abnormal reverse clutch pressure
Abnormal low and reverse brake pressure
Malfunction of the low and reverse solenoid valve
Malfunction of the reverse clutch
Malfunction of the low and reverse brake
Malfunction of the valve body

INSPECTION PROCEDURE 9
Shocks when changine from N to D, N to R and large time lag
Possible cause
If abnormal shocks or a time lag of 2 seconds or more occurs when the selector lever is shifted from N to D, N to R range while the engine is idling, the cause may be abnormal line pressure or a malfunction of the oil pump or valve body.
Abnormal line pressure
Malfunction of the oil pump
Malfunction of the valve body

INSPECTION PROCEDURE 10
Shocks and running up
Possible cause
If shocks occur when driving due to upshifting or downshifting and the transaxle speed becomes higher than the engine speed, the cause may be abnormal line pressure or a malfunction of a solenoid valve, oil pump, valve body or of a brake or clutch.
Abnormal line pressure
Malfunction of each solenoid valve
Malfunction of the oil pump
Malfunction of the valve body
Malfunction of each brake or each clutch

INSPECTION PROCEDURE 11
All points (Displaced shifting points)
Possible cause
If all shift points are displaced while driving, the cause may be a malfunction of the output shaft speed sensor, TPS or a solenoid valve.
Malfunction of the output shaft speed sensor
Malfunction of the throttle position sensor
Malfunction of each solenoid valve
Abnormal line pressure
Malfunction of the valve body
Malfunction of the TCM

INSPECTION PROCEDURE 12
Some points (Displaced shifting points)
Possible cause
If some of the shift points are displaced while driving, the cause may be a malfunction of the valve body, or it is related to control and is not an abnormality.
Malfunction of the valve body

INSPECTION PROCEDURE 13
No diagnostic trouble codes (Does not shift)
Possible cause
If shifting does not occur while driving and no diagnostic trouble codes are given, the cause may be a malfunction of the Park/Neutral position switch, or TCM.
Malfunction of the Park/Neutral position switch
Malfunction of the TCM

INSPECTION PROCEDURE 14
Poor acceleration
Possible cause
If acceleration is poor even if downshifting occurs while driving, the cause may be a malfunction of the engine system or of a brake or clutch.
Malfunction of the engine system
Malfunction of the brake or clutch

INSPECTION PROCEDURE 15
Vibration
Possible cause
If vibration occurs when driving at constant speed or when accelerating in top range, the cause may be abnormal torque converter clutch pressure or a malfunction of the engine system, torque converter clutch solenoid, torque converter or valve body.
Abnormal torque converter clutch pressure
Malfunction of the engine system
Malfunction of the torque converter clutch solenoid
Malfunction of the torque converter
Malfunction of the valve body