Inspection Procedure 9

COMMENT
If shift shocks when driving due to upshifting or downshifting and the transaxle speed becomes higher than the engine speed, the cause is probably abnormal line pressure or a malfunction of a solenoid valve, oil pump, valve body or of a brake or clutch.

TROUBLESHOOTING HINTS
The most likely causes for this case:
- Abnormal line pressure
- Malfunction of each solenoid valve
- Malfunction of the oil pump
- Malfunction of the valve body
- Malfunction of the each brake or each clutch
- Malfunction of the PCM

DIAGNOSIS





Required Special Tool: MB991502: Scan Tool (MUT-II)

CAUTION: To prevent damage to scan tool MB9911502, always turn the ignition switch to "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.

STEP 1. Using Scan Tool MB991502, Carry Out Actuator Test.
1. Connect scan tool MB991502 to the data link connector.
2. Check the following items in the actuator test. Refer to Actuator Test Reference Table.
a. Item 1: Low-reverse solenoid valve
b. Item 2: Underdrive solenoid valve
c. Item 3: Second solenoid valve
d. Item 4: Overdrive solenoid valve
3. Check that the solenoid valves click.
If the solenoids click, go to Step 2.
If the clicks cannot be heard, repair or replace the solenoids. Refer to Valve Body. Then confirm that the symptom is eliminated.

STEP 2. Adjust The Line Pressure.
Adjust the line pressure. Refer to Line Pressure Adjustment. Adjustments Then check for the symptom.
If the symptom is eliminated, go to Step 3.
If the symptom is not eliminated, go to Step 4.

STEP 3. Check Each Brake And Clutch.





Remove the transaxle.
Check the facing for seizure and piston seal ring for damage and interference with retainer. Repair or replace the faulty parts. Refer to Underdrive Clutch, Input Shaft, Reverse and Overdrive Clutch. Then check for the symptom.
If the symptom is eliminated, diagnosis is complete.
If the symptom is not eliminated, go to Step 6.

STEP 4. Replace The Oil Pump.





Remove the transaxle.
Replace the oil pump. (Oil pump can not be repaired). Then check for the symptom.
If the symptom is eliminated, diagnosis is complete.
If the symptom is not eliminated, go to Step 5.

STEP 5. Disassemble And Clean The Valve Body.





Check the O-ring installation bolts for looseness and valve and body for damage. Repair or replace the faulty parts. Refer to Valve Body.
If repair is not possible, replace the valve body assembly. Then check for the symptom.
If the symptom is eliminated, diagnosis is complete.
If the symptom is not eliminated, go to Step 6.

STEP 6. Replace The PCM.
Replace the PCM. The immobilizer-ECU and the ignition key should be replaced together with it. Refer to Ignition Switch and Immobilizer System - Ignition Switch and Immobilizer System. Confirm that the malfunction symptom is eliminated.
If malfunction is eliminated, diagnosis is complete.