NO.9 ABNORMAL SHIFTING [AY6A-EL, AY6AX-EL]

id0503k3801400

9

Abnormal shifting

DESCRIPTION

•  Shift incorrectly (incorrect shift pattern).

POSSIBLE CAUSE

•  There is a malfunction in the signal circuit which controls shifting (Accelerator opening signal, input/turbine speed sensor, VSS), the control valve is stuck, or the clutch circuit is stuck.

―  Clutch slippage, burnt (C1 clutch, C2 clutch, C3 clutch, B1 brake)

•  Line pressure low

•  Incorrect accelerator opening signal

•  VSS malfunction

•  Input/turbine speed sensor malfunction

•  Sensor ground malfunction

•  Shift solenoid C malfunction

•  Shift solenoid D malfunction

•  Shift solenoid E malfunction

•  Line pressure control solenoid malfunction

•  TCC control solenoid malfunction

•  Shift solenoid F malfunction

•  Body ground malfunction

•  Control valve body malfunction

―  Wheel speed signal malfunction

•  Tire of a different diameter from the standard tire is installed

•  ABS wheel-speed sensor malfunction

Note

•  Before following the troubleshooting steps, make sure that the Automatic Transaxle On-Board Diagnostic and Automatic Transaxle Basic Inspection are conducted. (See BASIC INSPECTION [AY6A-EL, AY6AX-EL].)

•  If a tire of a different diameter from the standard tire is installed, the TCM determines that the driving mode is the AAS mode, and may change to a different shift timing from the normal timing.

Diagnostic procedure

STEP	INSPECTION		ACTION
1	• Inspect the tire size and air pressure. • Is the tire of specified size and air pressure?	Yes	Go to the next step.
1		No	Replace with a specified tire size or adjust the air pressure of each specified tire to the specified value.
2	• Display the following DSC CM PIDs using the M-MDS. (See ON-BOARD DIAGNOSIS [DSC/RSC].) ― WSPD_LF ― WSPD_LR ― WSPD_RF ― WSPD_RR • Are the monitoring values displayed uniformly while driving?	Yes	Go to the next step.
2		No	Perform the following inspections: ABS wheel-speed sensor installation inspection ― Is the ABS wheel-speed sensor installation normal? ABS sensor rotor installation inspection ― Is the ABS sensor rotor installed twisted? (may cause output of abnormal wave pattern at high speeds.) ― Are there missing teeth on the sensor rotor? If there is any malfunction, repair or replace the malfunctioning location.
3	• Inspect for continuity between the TCM terminal A9 and battery negative terminal. • Is there continuity?	Yes	Go to the next step.
3		No	Repair or replace ground circuit.
4	• Inspect following shift solenoids. ― Shift solenoid C (See SHIFT SOLENOID C INSPECTION [AY6A-EL, AY6AX-EL].) ― Shift solenoid D (See SHIFT SOLENOID D INSPECTION [AY6A-EL, AY6AX-EL].) ― Shift solenoid E (See SHIFT SOLENOID E INSPECTION [AY6A-EL, AY6AX-EL].) ― Line pressure control solenoid (See LINE PRESSURE CONTROL SOLENOID INSPECTION [AY6A-EL, AY6AX-EL].) ― TCC control solenoid (See TORQUE CONVERTER CLUTCH (TCC) CONTROL SOLENOID INSPECTION [AY6A-EL, AY6AX-EL].) ― Shift solenoid F (See SHIFT SOLENOID F INSPECTION [AY6A-EL, AY6AX-EL].) • Are they normal?	Yes	Go to the next step.
4		No	Inspect the coupler component. If normal, replace the control valve body. (See CONTROL VALVE BODY REMOVAL/INSTALLATION [AY6A-EL, AY6AX-EL].)
5	• Inspect the ATF condition. (SeeAUTOMATIC TRANSAXLE FLUID (ATF) INSPECTION [AY6A-EL, AY6AX-EL].) • Is the ATF condition normal?	Yes	Inspect the TCM terminal for bend, damage, corrosion or poor contact.
5		No	Replace the transaxle. (See AUTOMATIC TRANSAXLE REMOVAL/INSTALLATION [AY6A-EL, AY6AX-EL].)
6	• Verify test results. ― If normal, return to the diagnostic index to service any additional symptoms. ― If malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis. • If the vehicle is repaired, troubleshooting completed. • If the vehicle is not repaired or additional diagnostic information is not available, replace the TCM.