Tools Required

J 21867 Pressure Gage

Line pressures are calibrated for two sets of gear ranges--Drive-Park-Neutral and Reverse. This allows the transmission line pressure to be appropriate for different pressure needs in different gear ranges:

Before performing a line pressure check, verify that the pressure control (PC) solenoid for the transmission is receiving the correct electrical signal from the PCM:

1. Install a Scan Tool .

Caution: Keep the brakes applied at all times in order to prevent unexpected vehicle motion. Personal injury may result if the vehicle moves unexpectedly.

Important: The transmission may experience harsh, soft or mushy shifts for up to two days later.

2. Start the engine and set the parking brake.
3. Check for diagnostic trouble codes, including a stored diagnostic code for the PC solenoid.
4. Repair the vehicle if necessary. Include the following areas:

•	Inspect the fluid level.

•	Inspect the manual linkage at the transmission.

•	Install or connect the Scan Tool .

•	Install or connect the J 21867 at the line pressure tap.

5. Put the gear selector in Park and set the parking brake.
6. Start the engine and allow the engine to warm up at idle.
7. Access the PCS Control test on the Scan Tool .
8. Increase DESIRED PCS in 0.1 amp increments. Read the corresponding line pressure on the J 21867 . Allow the pressure to stabilize for five seconds after each current charge.
9. Compare your data to the Drive-Park-Neutral line pressure table below.

If your pressure readings differ greatly from the line pressure table, refer to the Diagnosis Tables.

The Scan Tool is only able to control the PC solenoid in Park and Neutral with the vehicle stopped. This protects the clutches from extremely high or low pressures in Drive or Reverse ranges.

Refer to the Line Pressure table. The pressures in the table assume an engine speed of 1,500 RPM and a temperature of 66°C (150°F). The pressure will vary with a change in temperature.