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A/T - 4L30E Cold Shift Pattern

File In Section: 07 - Transmission/Transaxle

Bulletin No.: 01-07-30-001

Date: January, 2001

INFORMATION

Subject:
Cold Shift Pattern (Normal Condition)

Models:
1997-2001 Cadillac Catera
with Hydra-matic 4L30-E (RPO ML4)

Some owners of the above vehicles may comment on increased or higher engine speeds when the vehicle is driven immediately from a cold start. The Transmission Control Module (TCM) software contains a function that modifies shift speed speeds when the engine is cold. When activated, this feature will delay the shifts 10 to 15 km/h (6 to 9 mph), depending on the throttle angle.

The cold shift pattern enables if all of the following conditions exist:

^ The engine has been running for 5 seconds.
^ The engine temperature is between 40°C and +30°C (-40°F and +86°F).
^ Vehicle speed is 0 km/h (0 mph).

The cold shift pattern is disabled under any of the following conditions:

^ 60 seconds after activation.
^ If throttle angle exceeds 60.5 percent.
^ Vehicle speed exceeds 50 km/h (30 mph).

This is a normal condition, no repair should be attempted.





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