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A/T - 4T40E Clearing Shift Adapts

File In Section: 07 - Transmission/Transaxle

Bulletin No.: 01-07-30-024

Date: July, 2001

INFORMATION

Subject:
Clearing Shift Adapts

Models:
2002 Chevrolet Cavalier
2002 Oldsmobile Alero
2002 Pontiac Grand Am, Sunfire
With 2.2 L Engine (VINS F, 4 - RPOs L61, LN2) and
4T40-E Automatic Transmission (RPO MN4)

The above 2002 vehicles, with either the LN2 or L61 engines, have software that does not allow the Tech 2 to display or clear shift adapts. Even though the shift adapts will not display, they will function as expected. Shift adapts modify line pressure and MUST be cleared during any significant transmission repair.

Important:
If the adapts are not cleared, the vehicle may experience either soft or harsh shifts after a major repair.

To clear the shift adapts, it is necessary to disconnect power to the Powertrain Control Module (PCM) for 35 minutes. Refer to the Powertrain Control Module (PCM) Replacement procedure in the appropriate Service Manual.





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