Inspection Procedure 2

INSPECTION PROCEDURE 2: Does not Move Forward

COMMENT

If the engine is idling and the selector lever is shifted from "N" to "D" range and the vehicle does not drive forward then the cause is due to line pressure defect, under drive clutch or valve body malfunction.

TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CONDITION:)

- Abnormal line pressure
- Malfunction of the underdrive solenoid valve
- Malfunction of the underdrive clutch
- Malfunction of the oil pump
- Malfunction of the valve body
- Malfunction of the PCM

DIAGNOSIS

Required Special Tools:

- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A

STEP 1. Using scan tool MB991958, check actuator test item 2: Underdrive Solenoid Valve.





(1)
CAUTION:
To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK"
(OFF) position before connecting or disconnecting scan tool MB991958.

Connect scan tool MB991958 to the data link connector.
(2)Turn the ignition switch to the "ON" position.
(3)Set scan tool MB991958 to the actuator test mode.

- Item 2: Underdrive Solenoid Valve.
- An audible clicking or buzzing should be heard when the underdrive solenoid valve is energized.
(4)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is the solenoid valve operating properly?

YES Go to Step 2.

NO Replace the torque converter. Transaxle Disassembly and Assembly [4A/T]
or [5A/T].

STEP 2. Check the hydraulic pressure.

Shift the selector lever to the sport mode then measure the hydraulic pressure of each element in 1st speed to check and see if each respective hydraulic pressure is within the range of standard pressure. Refer to Hydraulic Pressure Test, Hydraulic Pressure Test.

Q. Is the hydraulic pressure within the standard value?

YES Go to Step 3.
NO Go to Step 4.
STEP 3. Check the underdrive clutch system.

(1)Remove the valve body cover and valve body. Transaxle Disassembly and Assembly [4A/T]
or [5A/T].





(2)Blow 108 kPa (15psi) compressed air into the underdrive clutch oil orifice of the transaxle case, and check if the underdrive clutch piston moves and air pressure is maintained in that condition.

Q. Is the air pressure maintained?

YES Go to Step 4.

NO Go to Step 6.

STEP 4. Disassemble and clean the valve body.





Check the O-ring installation bolts for looseness and valve body for damage. Repair or replace the faulty parts. Valve Body Disassembly and Assembly [4A/T]
or [5A/T].
Replace the valve body assembly if the damage is too extensive. Then check the symptom.

Q. Is the symptom eliminated?

YES The procedure is complete.

NO Go to Step 5.

STEP 5. Check the oil pump.

(1)Remove the transaxle assembly.





(2)Check the oil pump (incorrect installation, damage and etc.) and replace the oil pump assembly if necessary (The oil pump cannot be disassembled). Transaxle Disassembly and Assembly [4A/T]
or [5A/T]. Then check the symptom.

Q. Is the symptom eliminated?

YES The procedure is complete.

NO Go to Step 7.

STEP 6. Check the underdrive clutch.

(1)Remove the transaxle assembly.





(2)Check the facing for seizure and the piston seal ring for damage and interference with the retainer. Repair or replace the faulty parts. Underdrive Clutch and Input Shaft Disassembly and Assembly [4A/T] or [5A/T]. Then check the symptom.

Q. Is the symptom eliminated?

YES The procedure is complete.

NO Go to Step 7.

STEP 7. Replace the PCM.

When the PCM is replaced, register the encrypted code. Immobilizer System.

Q. Is the symptom eliminated?

YES The procedure is complete.
NO Start over at Step 1.