| Subject: | Clearing Shift Adapts |
| Models: | 2002 Chevrolet Cavalier |
| 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.
