Engagement Delay Test
Engagement Delay Test
Purpose/Description of Test
Engagement delay is the time delay in seconds that it takes 1 to feel the slight engagement of the automatic transmission assembly into gear. The engagement delay test starts when the automatic transmission gearshift selector is moved from the PARK to the REVERSE or DRIVE positions. This test can also be performed by starting in the NEUTRAL position and then shifting to the DRIVE or REVERSE positions. Engagement delay times can be used to diagnose the hydraulic system and internal clutch conditions/concerns.
Conditions
^ Verify that the automatic transmission fluid (ATF) temperature is between 50-80°C (120-176°F).
^ All additional electrical loads are OFF.
^ The engine is at, and maintains, a base idle.
Procedure
1. Chock all 4 wheels and fully apply the parking brake in order to prevent any vehicle movement during testing.
Important:
^ Perform each test 3 times and take the average value.
^ Maintain a time interval of greater than 1 minute between engagement delay tests. The 1 minute delay allows release of clutch fluid pressure.
^ After servicing any of the following, clear the adapt learn data and perform adapt learn procedure. Programming and Relearning Poor transaxle performance will occur without completing the adapt learn. Refer to Transmission Adaptive Functions.
^ Control valve body replacement
^ TCM replacement
^ TCM calibration change
^ Transaxle replacement
^ The adapt learn procedure requires repeat shifting the transaxle from Neutral to Drive to Neutral 5 times. Then repeat shifting from Neutral to Reverse to Neutral 5 times. While in Drive or Reverse, hold in that range for a minimum of 3 seconds.
2. Begin the test by using a time recording device, starting the device at the moment when the automatic transmission gearshift selector is moved from either the PARK or the NEUTRAL position to either the REVERSE or the DRIVE position.
Engagement Delay Test Results:
3. The time recording device is stopped at the exact moment that the automatic transmission is felt to have engaged into the selected gear.
^ PARK or NEUTRAL to DRIVE position: Less than 0.7 seconds
^ PARK or NEUTRAL to REVERSE position: Less than 1.2 seconds