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NO.6 LOW MAXIMUM SPEED AND POOR ACCELERATION [JA5A-EL]

BME050301030242

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, the malfunction is in the engine circuit.

  1. Clutch slippage, burnt

  • Line pressure low
  • Incorrect throttle position signal
  • VSS malfunction
  • Input/turbine speed sensor malfunction
  • Sensor GND malfunction
  • Shift solenoids A, B, or C malfunction
  • Body GND malfunction
  • Control valve body malfunction

  2. Transaxle fixed in 4GR (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

  3. Insufficient starting torque (Suspected when in-gear condition, shift control and engine circuit are normal)

  • Torque converter malfunction (Poor operation, stuck)

  4. Engagement of TCC operation range (Operation of fail-safe function)

  • TFT sensor malfunction (Short or open circuit)

  Note

  • Before following the troubleshooting steps, make sure that the Automatic Transaxle On-Board Diagnostic and Automatic Transaxle Basic Inspection are conducted.

Diagnostic procedure

STEP | INSPECTION | ACTION
--- | --- | ---
1 | With ignition switch at the ON position, does the HOLD indicator light indication correspond to the HOLD switch operation? | Yes | Go to the next step.
No | Go to No.26 "HOLD INDICATOR LIGHT DOES NOT ILLUMINATE WHEN HOLD SWITCH IS TURNEDTO ON", or No.27 "HOLD INDICATOR LIGHT ILLUMINATE WHEN HOLD SWITCH IS NOT TURNED TO ON".
2 | Go to No.12 "LACK/LOSS OF POWER-ACCELERATION/CRUISE". (See NO.12 LACK/LOSS OF POWER-ACCELERATION/CRUISE [AJ] (VIN: JMZ LW19J7*# 300001-, JM0 LW10J300 300001-301405, JM6 LW10J300 300001-, JM8 LW28J**# 300001-301513).) (See NO.12 LACK/LOSS OF POWER-ACCELERATION/CRUISE [AJ] (VIN: JM0 LW10J300 301406-, JMZ LW69J7*# 307683-, JM8 LW28J**# 301514-, JM8 LW28A**# 301514- (Assumed)).)
Does the 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 the shift solenoid A, B, and C. Are they normal? | Yes | Go to the next step.
No | Inspect for stuck shift solenoid. (See SOLENOID VALVE INSPECTION [JA5A-EL].) If shift solenoids is normal, inspect for open or short circuit between TCM terminals 2W, 2T, 2X and pressure control solenoid terminals I, G, or F.
4 | Remove the torque converter. Inspect the torque converter. (See ATX Workshop Manual.) Is the torque converter normal? | Yes | Overhaul the control valve body and repair or replace any malfunctioning parts. (See ATX Workshop Manual.) If any problem remains, replace or overhaul the transaxle and repair or replace any malfunctioning parts. (See AUTOMATIC TRANSAXLE REMOVAL/INSTALLATION [JA5A-EL].)
(See ATX Workshop Manual.)
No | Replace the torque converter.
5 | • Verify the test results.

  - If normal, return to the diagnostic index to service any additional symptoms.
  - If the malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis.

  • If the vehicle is repaired, troubleshooting is completed.
  • If the vehicle is not repaired or additional diagnostic information is not available, replace the TCM.