GM Service Manual Online
For 1990-2009 cars only

TFP Manual Valve Position Switch Logic

Range Signal

A

B

C

Park/Neutral

LOW

HI

HI

Reverse

LOW

HI

LOW

D4

LOW

LOW

HI

D3

HI

LOW

HI

D2

HI

LOW

LOW

D1

LOW

LOW

LOW

Invalid

HI

HI

HI

Invalid

HI

HI

LOW

LOW = 0 volts

HI = Ignition voltage