NO.6 LOW MAXIMUM SPEED AND POOR ACCELERATION [AY6A-EL, AY6AX-EL]

id0503k3801100

6
Low maximum speed and poor acceleration
DESCRIPTION
•  Vehicle acceleration is poor at start.
•  Delayed acceleration when accelerator pedal is depressed while driving.
POSSIBLE CAUSE
•  If the clutch is stuck or does not stay in 4GR, malfunction is in engine circuit.
―  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 A malfunction
•  Shift solenoid B malfunction
•  Shift solenoid C malfunction
•  Shift solenoid D malfunction
•  Shift solenoid E malfunction
•  Line pressure control solenoid malfunction
•  Shift solenoid F malfunction
•  Body ground malfunction
•  Control valve body malfunction
―  Transaxle fixed in 3GR or 5GR* (Operation of fail-safe function)
•  Short or open circuit in wiring harness
•  Poor connection of connector
•  Malfunction of electronic parts of output and input system
―  Insufficient starting torque (Suspected when in-gear, shift control and engine circuit are normal)
•  Torque converter malfunction (Poor operation, stuck)
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].)

Diagnostic procedure

STEP

INSPECTION

ACTION
1
•  With the ignition switch at the ON position, does the gear position indicator light indication correspond to the selector lever position?
Yes
Go to the next step.
No
Go to No.27 “GEAR POSITION INDICATOR LIGHT DOES NOT ILLUMINATE IN D OR M POSITION”, or No.28 “GGEAR POSITION INDICATOR LIGHT ILLUMINATE IN P, R OR N POSITION”.
2
•  Go to No.12 “LACK/LOSS OF POWER (ACCELERATION/CRUISE)”.
•  Does engine control system normal?
Yes
Go to the next step.
No
Repair or replace any malfunctioning parts according to the inspection results.
3
•  Stop the engine.
•  Inspect following solenoid.
―  Shift solenoid A
―  Shift solenoid B
―  Shift solenoid C
―  Shift solenoid D
―  Shift solenoid E
―  Shift solenoid F
―  Line pressure control solenoid
•  Are they normal?
Yes
Go to the next step.
No
Inspect the coupler component.
If normal, replace the control valve body.
(See CONTROL VALVE BODY REMOVAL/INSTALLATION [AY6A-EL, AY6AX-EL].)
4
•  Perform the stall test.
•  Is the stall speed within the specified?
Yes
Inspect the ATF condition.
If large amount of metal specks are found, replace the transaxle.
(See AUTOMATIC TRANSAXLE REMOVAL/INSTALLATION [AY6A-EL, AY6AX-EL].)
If a large amount of metal specks are not found, replace the control valve body.
(See CONTROL VALVE BODY REMOVAL/INSTALLATION [AY6A-EL, AY6AX-EL].)
No
Replace the torque converter.
(See TORQUE CONVERTER REMOVAL/INSTALLATION [AY6A-EL, AY6AX-EL].)
5
•  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.

*  :If case of shift solenoid C failure