DIAGNOSIS Required Special Tool: • MB991958: Scan Tool (MUT-III Sub Assembly) MB991824: V.C.I. MB991827: MUT-III USB Cable MB991911: MUT-III Main Harness B

STEP 1. Using scan tool MB991958, read the A/T diagnostic trouble code.

To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958. (1) Connect scan tool MB991958 to the data link connector. (2) Turn the ignition switch to the "ON" position. (3) Check for A/T diagnostic trouble code. (4) Turn the ignition switch to the "LOCK" (OFF) position. Q: Is DTC 22 or 36 set? YES <DTC 22 set>: Refer to , DTC 22: Input Shaft Speed Sensor System. YES <DTC 36 set>: Refer to , DTC 36: Torque Converter Clutch Solenoid Valve System. NO: Go to Step 2 .

STEP 2. Using scan tool MB991958, check data list item 36: Torque Converter Clutch Solenoid Valve Duty%.

To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958. (1) Connect scan tool MB991958 to the data link connector. (2) Start the engine. (Warming up engine) (3) Set scan tool MB991958 to the data reading mode. Item 36: Torque Converter Clutch Solenoid Valve Duty%. When driving at constant speed of 60 km/h (37 mph), the display should be "70 - 99.6%" (Gear range: 3rd gear). When the accelerator pedal is released [at less than 50 km/h (31 mph)], the display should be "70 - 99.6% ► 0%" (decreases gradually as the vehicle speed decreases) (Gear range: 3rd gear). (4) Turn the ignition switch to the "LOCK" (OFF) position. Q: Is the solenoid valve operating properly? YES: Go to Step 3 . NO: Go to Step 5 .

STEP 3. Using scan tool MB991958, check data list item 52: Torque Converter Clutch Amount of Slippage.

To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958. (1) Connect scan tool MB991958 to the data link connector. (2) Start the engine. (Warming up engine) (3) Set scan tool MB991958 to the data reading mode. Item 52: Torque Converter Clutch Amount of Slippage. Driving at a constant speed of 60 km/h (37 mph), the display should be "-10 to 10 r/min." If the accelerator pedal is released, the display on the scan tool changes (50 km/h (31 mph) and less). (4) Turn the ignition switch to the "LOCK" (OFF) position. Q: Is the clutch operating properly? YES: Go to Step 4 . NO: Go to Step 5 .

STEP 4. Using scan tool MB991958, read the A/T diagnostic trouble code.

To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958. (1) Connect scan tool MB991958 to the data link connector. (2) Turn the ignition switch to the "ON" position. (3) Check for A/T diagnostic trouble code. (4) Turn the ignition switch to the "LOCK" (OFF) position. Q: Is DTC 52 set? YES: Replace the PCM. NO: The procedure is complete.

STEP 5. Check the hydraulic pressure (for torque converter). Measure the hydraulic pressure for torque converter. Check if the hydraulic pressure is within the standard value. Refer to , Hydraulic Pressure Test. Q: Is the hydraulic pressure within the standard value? YES: Go to Step 7 . NO: Go to Step 6 .

STEP 6. Adjust line pressure. Adjust line pressure. Refer to , Line Pressure Adjustment. Then check the symptom. Q: Is the symptom eliminated? YES: The procedure is complete. NO: Go to Step 8 .

STEP 7. Replace the PCM. Q: Is the symptom eliminated? YES: The procedure is complete. NO: Go to Step 8 .