NO.18 EXCESSIVE SHIFT SHOCK IS GIVEN WHEN UPSHIFTING AND DOWNSHIFTING [AW6A-EL, AW6AX-EL]


id050310802300

18
Excessive shift shock is given when upshifting and downshifting
DESCRIPTION
•  Excessive shift shock is felt when depressing the accelerator pedal at upshifting.
•  During cruising, excessive shift shock is felt when depressing accelerator pedal at downshifting.
POSSIBLE CAUSE
•  Shift shock may worsen when the fail-safe is operating. The shift shock may worsen if the accelerator pedal position sensor, APP sensor, input/turbine speed sensor, or VSS signal malfunctions.
―  Clutch slippage, burnt (C1 clutch, C2 clutch, C3 clutch, B1 brake)
•  Line pressure low, high
•  Incorrect accelerator opening signal
•  VSS malfunction
•  Input/turbine speed sensor malfunction
•  TFT sensor 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 GND and sensor GND malfunction
•  Coupler component malfunction
•  Control valve body malfunction
―  Poor hydraulic operation (Malfunction in range change)

Diagnostic procedure

STEP

INSPECTION

ACTION

1
•  Inspect for continuity between the TCM terminal A9 and battery negative terminal.
•  Is there continually?
Yes
Go to the next step.
No
Repair or replace ground circuit.
2
•  Perform the PID/DATA Monitor Record Procedure and access the following PCM and TCM PIDs while excessive shift shock condition.
PCM PIDs:
―  APP
―  TP
TCM PIDs:
―  SSF
―  LPS
―  TCCC
―  TSS
―  OSS
•  Are there normal?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results.
3
•  Stop the engine.
•  Inspect the solenoid.
―  Shift solenoid C
―  Shift solenoid D
―  Shift solenoid E
―  Line pressure control solenoid
•  Are there normal?
Yes
Inspect the ATF condition.
If a large amount of metal specks are found:
•  Overhaul the transaxle.
(See Automatic Transaxle and Transfer Workshop Manual AW6A-EL AW6AX-EL.)
•  Repair or replace the any malfunctioning parts.
If a large amount of metal specks are not found:
•  Replace the control valve body.
No
Inspect the coupler component.
If normal, replace the control valve body.
4
•  Verify test results.
―  If normal, return to the diagnostic index to service any additional symptoms.
―  If malfunction remains, inspect the related Service Information and perform repair or diagnosis.
•  If vehicle is repaired, troubleshooting completed.
•  If the vehicle is not repaired or additional diagnostic information is not available, replace the TCM.