Shift Point Tests (Road Test)

ROAD TESTING VEHICLE
The Shift Point Road Test and Torque Converter Clutch Operation Test provide diagnostic information on transmission shift controls and torque converter operation.

SHIFT POINT ROAD TEST

NOTE: Always drive the vehicle in a safe manner according to driving conditions and obey all traffic laws.

E4OD Applications Shift Speeds - Approximate* MPH:

This test verifies that the shift control system is operating properly.
1. Bring engine and transmission up to normal operating temperature.
2. Operate the vehicle with the transmission range selector lever in (OD) range.
3. Apply minimum throttle and observe the speeds at which the upshift occurs and the torque converter engages. (Refer to Automatic Transmission Special Specification Bulletin FPS-12180-98 for actual speed.)
4. With the vehicle in OVERDRIVE (fourth gear), depress the transmission control switch. The transmission should downshift to third gear. Remove foot from accelerator pedal; engine braking should occur.
5. Press accelerator pedal to floor (wide-open throttle (WOT)). Transmission should shift from third to second gear or third to first, depending on vehicle speed. Torque Converter Clutch (TCC) should disengage and then reapply.
6. With vehicle (OD) range above 80 km/h (50 mph) and less than half throttle, move the transmission range selector lever from (OD) range to MANUAL 2 range and remove foot from accelerator pedal. The transmission should immediately downshift into second gear. With the vehicle remaining in MANUAL 2 range, move transmission range selector lever into MANUAL 1 range. Transmission should downshift into first gear at speeds BELOW 48 - 56 km/h (30 - 35 mph).
7. If transmission fails to upshift/downshift or TCC does not apply and release, refer to Diagnosis by Symptom Index for concern diagnosis. Symptom Related Diagnostic Procedures

TORQUE CONVERTER DIAGNOSIS
Prior to torque converter replacement, all diagnostic procedures must be followed. This is to prevent the unnecessary replacement of good torque converters. Only after a complete diagnostic evaluation can the decision be made to replace the torque converter.
Begin with the normal diagnostic procedures as follows:
1. Preliminary Inspection.
2. Know and Understand the Customer's Concern.
3. Verify the Concern - Perform the Torque Converter Clutch Operation Test.
4. Perform Diagnostic Procedures.
- Run on-board diagnostics.
^ Repair all non-transmission-related Diagnostic Trouble Codes (DTCs) first.
^ Repair all transmission DTCs.
^ Rerun on-board diagnostics to verify repair.
- Perform Line Pressure Test.
- Perform Stall Speed Test.
- Perform Diagnostic Routines. Diagnostic Routines
^ Use the Diagnosis by Symptom Index to locate the appropriate routine that best describes the symptom(s). The routine will list all possible components that may cause or contribute to the symptom. Check each component listed; diagnose and repair as required, before repairing the torque converter. Diagnosis By Symptom Index

TORQUE CONVERTER CLUTCH OPERATION TEST
This test verifies that the Torque Converter Clutch (TCC) control system and the torque converter are operating properly.
1. Perform Quick Test. Check for Diagnostic Trouble Codes (DTCs). Refer to Diagnostic Trouble Code Chart. Testing and Inspection
2. Connect a tachometer to the engine.
3. Bring the engine to normal operating temperature by driving the vehicle at highway speeds for approximately 15 minutes in (OD) position.
4. After normal operating temperature is reached, maintain a constant vehicle speed of about 80 km/h (50 mph) and tap brake pedal with the left foot.
5. Engine rpm should increase when brake pedal is tapped, and decrease about five seconds after pedal is released. If this does not occur, refer to Torque Converter Operation Concerns in the Diagnosis by Symptom Index. Testing and Inspection
6. If the vehicle stalls in (OD) or MANUAL 2 at idle with vehicle at a stop, move the Transmission Range (TR) selector lever to MANUAL 1 position. If the vehicle stalls, refer to Torque Converter Operation Concerns in the Diagnosis by Symptom Index. Repair as required. If the vehicle does not stall in (OD), refer to Diagnosis by Symptom. Testing and Inspection