GM Service Manual Online
For 1990-2009 cars only

Range

Pressure Switch 1 - N/O

Pressure Switch 2 - N/O

Pressure Switch 3 - N/O

Pressure Switch 4 - N/C

Switch Status

Scan Tool Status

Switch Status

Scan Tool Status

Switch Status

Scan Tool Status

Switch Status

Scan Tool Status

R

Open

HIGH*

Closed

LOW

Closed

LOW

Closed

LOW

N

Closed

LOW

Closed

LOW

Closed

LOW

Open

HIGH

1

Open

HIGH

Closed

LOW

Open

HIGH

Open

HIGH

2

Open

HIGH

Open

HIGH

Open

HIGH

Open

HIGH

3

Closed

LOW

Open

HIGH

Open

HIGH

Open

HIGH

4

Closed

LOW

Open

HIGH

Closed

LOW

Open

HIGH

5

Open

HIGH

Open

HIGH

Closed

LOW

Open

HIGH

6

Open

HIGH

Open

HIGH

Closed

LOW

Open

HIGH

N/C = Normally Closed

N/O = Normally Open

* Pressure switch 1 (PS1) reverts to the Closed/LOW state with throttle applied in REVERSE.