Time Lag Test - Toyota Hilux Surf 1993 Owner's Manual

TIME LAG TEST

When the shift lever is shifted while the engine is idling, there will be a certain time lapse or lag before the
shock can be felt. This is used for checking the condition of the O/D direct clutch, front clutch, rear clutch
and No.3 brake.
NOTICE:
Perform the test at normal operating fluid temperature (50–80E C or 122–176E F).
•
Be sure to allow one minute interval between tests.
•
Make three measurements and take the average value.
•
MEASURE TIME LAG
(a) Fully apply the parking brake.
(b) Start the engine and check the idle speed.
Idle speed: 750 RPM
(N position)
(c) Shift the shift lever from N to D position. Using a stop watch, measure the time it takes from
shifting the lever until the shock is felt.
Time lag: Less than 1.2 seconds
(d) In same manner, measure the time lag for N–R.
Time lag: Less than 1.5 seconds
EVALUATION
(a) If N–) D time lag is longer than specified:
Line pressure too low
Front clutch worn
O/D one–way clutch not operating properly
(b) If N–R time lag is longer than specified:
Line pressure too low
Rear clutch worn
No.3 brake worn
O/D one–way clutch not operating properly
AUTOMATIC TRANSMISSION – Troubleshooting (Mechanical System Tests)
AT–21