NO.18 EXCESSIVE SHIFT SHOCK IS FELT WHEN UPSHIFTING AND DOWNSHIFTING


18	Excessive shift shock is felt 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 the accelerator pedal at downshifting.
POSSIBLE CAUSE	• Shift shock may worsen when the fail-safe is operating. The shift shock has worsened if the TP sensor, input/turbine speed sensor, or vehicle speed sensor signal malfunctions. 1. Clutch slippage, burnt (Forward clutch, 2-4 brake band, 3-4 clutch) • Line pressure low, high • Shift solenoid D malfunction • Shift solenoid E malfunction • Shift solenoid A malfunction • Shift solenoid B malfunction • Shift solenoid C malfunction • Pressure control solenoid malfunction • Accelerator cable mis-adjustment • Control valve body malfunction • Body GND malfunction 2. Signal malfunction • Transaxle temperature sensor malfunction • Vehicle speed sensor malfunction • Sensor GND malfunction • TP sensor malfunction • Input/turbine speed sensor malfunction 3. Poor hydraulic operation (Malfunction in range change) • Pressure switch malfunction • Forward accumulator malfunction • Servo apply accumulator malfunction 4. Engine mounts installation • Loose attaching bolts • Worn parts Note • Before following the troubleshooting steps, make sure that the Automatic Transaxle On-Board Diagnostic and Automatic Transaxle Basic Inspection are conducted.


STEP	INSPECTION		ACTION
1	Inspect the engine mounts for loose tightening bolts or worn parts. Are all engine mounts normal?	Yes	Go to the next step.
1		No	Readjust, retighten or replace engine mounts.
2	Perform the stall test. (See Stall Test.) Is the stall speed normal?	Yes	Go to the next step.
2		No	Repair or replace any malfunctioning parts.
3	Inspect the value at the following PCM PID using the WDS or equivalent. (See PCM INSPECTION [ZY, Z6].) (See PCM INSPECTION [LF, L3].) • TP V Is the PID value normal?	Yes	Go to the next step.
3		No	Repair or replace any malfunctioning parts.
4	Disconnect the PCM connector. Is the resistance between the ground terminal at the PCM connector and the body ground less than 5.0 ohms?	Yes	Go to the next step.
4		No	Repair the open ground circuit. Reconnect the PCM.
5	Inspect the LPS PID value. Is the LPS PID value normal? (See PCM INSPECTION [ZY, Z6].) (See PCM INSPECTION [LF, L3].)	Yes	Overhaul the control valve body and repair or replace any malfunctioning parts. (See ATX workshop manual (FN4A-EL).) If any problem remains, overhaul the transaxle and repair or replace any malfunctioning parts. (See ATX workshop manual (FN4A-EL).)
5		No	Repair or replace any malfunctioning parts.
6	• Verify the test results. - If normal, return to the diagnostic index to service any additional symptoms. - If the malfunction remains, inspect the related Service 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 PCM.