GM Service Manual Online
For 1990-2009 cars only

Range

A

B

C

P

P

OFF

ON

ON

OFF

R Transitional

OFF

OFF

ON

OFF

R

OFF

OFF

ON

ON

N

ON

OFF

ON

OFF

D Transitional

ON

OFF

OFF

OFF

D

ON

OFF

OFF

ON

*M

OFF

OFF

OFF

OFF

D1 Transitional

OFF

ON

OFF

OFF

1

OFF

ON

OFF

ON

Invalid

ON

ON

ON

ON

Invalid

ON

ON

ON

OFF

Invalid

OFF

ON

ON

ON

Invalid

ON

OFF

ON

ON

Invalid

OFF

OFF

OFF

ON

Invalid

ON

ON

OFF

ON

ON = Open Circuit

OFF = Grounded Circuit

*M mode allows TAP Up/TAP Down feature functionally between 1st through 6th ranges.

In this range, logic states do not change.