Line Pressure Check
Special Tools
- J-21867: Pressure Gage
- J-21867-65: Pressure Test Adapter (5.3 Only)
For equivalent regional tools, refer to Special Tools .
- Before performing a line pressure check, verify that the pressure control (PC) solenoid valve is receiving the correct electrical signal from the PCM.
- Some conditions may be intermittent, therefore this test should be performed at least 3 times.
- Install a scan tool.
- Start the engine and set the parking brake.
- Check for a stored Diagnostic Trouble Code (DTC).
- Repair the vehicle, if necessary.
- Check the fluid level. Refer to the Transmission Fluid Check .
- Check the manual linkage for proper adjustment.
- Turn the engine Off.
- Loosen Exhaust cross-over pipe to allow attachment of J-21867-65: Pressure Test Adapter (5.3 Only).
- Remove the oil pressure test hole plug and install the J-21867: Pressure Gage and the J-21867-65: Adapter if used.
- Put the gear selector in PARK range and set the parking brake.
- Start the engine and allow the engine to warm up at idle.
- Access the PC solenoid valve control test on the scan tool.
- Increase the PC solenoid actual current from 0 to 1 amps in 0.1 amp increments. Allow the pressure to stabilize for five seconds after each pressure change. Read the corresponding line pressure on the J-21867: gage.
- Refer to the Line Pressure specification table. Compare the data to the table.
- If pressure readings differ greatly from the table, refer to Incorrect Line Pressure .
- Shut the engine OFF. Remove the J-21867: gage and J-21867-65: adapter if used.
- Apply sealant GM P/N 12345382 (Canadian P/N 1095348) to the oil pressure test hole plug.
- Install the oil pressure test hole plug and tighten to 12 N.m (106 lb in).
- Re-tighten the exhaust cross-over pipe (5.3 only).
NOTE:
WARNING:
Keep the brakes applied at all times in order to prevent unexpected vehicle motion. Personal injury may result if the vehicle moves unexpectedly.
CAUTION:
The total test running time should not be longer than 2 minutes. Running the test longer than 2 minutes may damage the transaxle.
CAUTION:
Refer to Fastener Caution
.