Operation CHARM: Car repair manuals for everyone.

Time Lag Test

Time Lag Test
If selector lever is shifted while engine is idling, there will be a certain time lapse, or time lag, before shock is felt. This step measures time lag to check condition of N-D, 1-2, and N-R accumulators; forward and one-way clutches; 2-4 brake band; and low and reverse brake.

Preparation
Follow preparation procedure outlined in Stall Test.

Procedure





1. Start engine.
2. Check idle speed in P range.
Idle speed: 750 - 850 rpm (with parking brake applied)
3. Shift from N range to D range.
4. Use a stopwatch to measure time it takes from shifting until shock is felt.
5. Shift selector to N range and run engine at idle speed for at least one minute.

Notice: Make three measurements for each test and take average value.

6. Perform test for following shifts in same manner.
a. N -> D range
b. N -> D range (O/D OFF mode)
c. N -> R range

Time lag: N -> D range 0.5 - 0.6 seconds
Time lag: N -> R range 0.6 - 0.7 seconds





Evaluation of time lag test