Excessive Shock Or Flares On 1-2 Upshift Or 2-1 Downshift

Excessive shock or flares on 1-2 upshift or 2-1 downshift

Diagnostic Procedure:

1. Shift solenoid valve D defective

2. A/T clutch pressure control solenoid valve A defective

3. A/T clutch pressure control solenoid valve B defective

4. A/T clutch pressure control solenoid valve C defective

5. 2nd clutch transmission fluid pressure switch defective

6. Foreign material in separator plate orifice

7. 1st accumulator defective

8. 2nd accumulator defective

9. 1st check ball stuck

10. 2nd check ball stuck

11. 1st clutch defective

12. 2nd clutch defective

13. Look up shift valve defective

Also check for:

- Check for a stored DTC, and check for loose connections.
- Test the solenoid valve function with the HDS.
- Inspect the A/T clutch pressure control solenoid valve body gasket, the ATF feed pipes, and the O-rings for wear and damage.
- Inspect shift solenoid valve D for seizure, and the O-rings for wear and damage.
- Check for a clogged orifice in the transmission fluid pressure switch connector. If the orifice is clogged, remove it, and clean the connector.
- Check for a clogged orifice in the separator plate. If the orifice is clogged, remove it, and clean the separator plate orifice.
- Check the ATF strainer for debris. If the strainer is clogged with particles of steel or aluminum, inspect the ATF pump. If the ATF pump is OK, find the damaged components that caused the debris. If no cause for contamination is found, replace the torque converter.
- Inspect the 1st accumulator piston, the O-ring, and the spring for wear and damage in the servo body.
- Inspect the 2nd accumulator piston, the O-ring, and the spring for wear and damage in the servo body.
- Check that the 1st check ball and the 2nd check ball are not stuck in the main valve body.
- Check the 1st and 2nd clutch pressures.
- Inspect the secondary shaft, the 1st clutch, and the 2nd clutch for wear and damage.
- Inspect the clutch piston, the clutch piston check valve, and the O-rings. Check the spring retainer for wear and damage. Inspect the clearance between the clutch end-plate and the top disc. If the clearance is out of tolerance, inspect the clutch discs and the plates for wear and damage, and inspect the clutch wave-plate height. If the discs and the plates are worn or damaged, replace them as a set. If the wave-plate height is out of tolerance, replace the wave-plate. If they are OK, adjust the clearance with the clutch end-plate.
- Inspect the 2nd clutch feed pipe. If the 2nd clutch feed pipe is scored, replace the end cover.
- Replace the secondary shaft if the bushing for the 2nd clutch feed pipe is loose or damaged.