Inspection Procedure 4
COMMENTIf the vehicle does not move forward or backward when the selector lever is shifted to any position while the engine is idling, the cause is probably abnormal line pressure, or a malfunction of the power train, oil pump or valve body.
TROUBLESHOOTING HINTS
The most likely causes for this case:
- Abnormal line pressure
- Malfunction of the power train
- Malfunction of the oil pump
- Malfunction of the valve body
- Low A/T fluid level
- Malfunction of the PCM
DIAGNOSIS
STEP 1. Check The Hydraulic Pressure.
Measure the hydraulic pressure of each element when the transaxle is in 1st, 2nd or reverse. Check if each hydraulic pressure is within the standard value. Refer to Hydraulic Pressure Test. Hydraulic Pressure Tests
If all are within the standard value, check A/T fluid level and condition. If not OK, repair or replace as necessary, then recheck symptom. If OK, go to Step 3.
If all are not within the standard value, go to Step 2.
If some elements are within the standard value and some are not, recheck the symptom.
STEP 2. Disassemble And Clean The Valve Body.
Check the O-ring installation bolts for looseness and the valve 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 4.
STEP 3. Check The Transaxle Power Train Components.
Disassemble the transaxle and check the planetary carrier, output shaft and differential, etc. Repair or replace the damaged parts. Refer to Planetary Carrier Assembly, Output Shaft, Differential. Then check for the symptom.
If the symptom is eliminated, diagnosis is complete.
If the symptom is not eliminated, go to Step 5.
STEP 4. Replace The Oil Pump.
Remove the transaxle. Replace the oil pump (Oil pump cannot 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. 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.