Vacuum Controls Test
WARNING: This page is about a different car, the 1998 Buick LeSabre. However, it is still accessible from the selected car via links, so may be relevant.
- Connect scan tool to DLC located beneath instrument panel. Turn ignition switch to ON position. Select DATA LIST. Observe vacuum solenoids No. 1, 2, 3 and 4. Press HEAT button on A/C-heater control panel. If vacuum solenoid No. 3 is on and vacuum solenoids No. 1, 2, and 4 are off, go to next step. If vacuum solenoids are not as specified, go to step 3).
- Press AUTO button. Press and hold TEMP button until set temperature decreases to 60°F (18°C). If vacuum solenoid No. 3 is off and vacuum solenoids No. 1, 2, and 4 are on, go to step 4). If vacuum solenoids are not as specified, inspect programmer connector for proper terminal contact. If terminals are okay, replace programmer.
- Using scan tool, select MISC. TESTS. Command vacuum solenoid No. 3 to come on. Select DATA LIST, and observe vacuum solenoid No. 3. If vacuum solenoid No. 3 is on, inspect A/C-heater control connector terminals for proper contact. If connector terminals are okay, replace A/C-heater control panel. If vacuum solenoid No. 3 is off, inspect programmer connector for proper terminal contact. If terminals are okay, replace programmer.
- Disconnect programmer vacuum connector, located under right side of instrument panel. Perform vacuum tests as specified. See Fig 1. If vacuum tests are as specified, temporarily substitute known-good programmer. Retest system. If a port holds vacuum but air does not flow from outlet, inspect associated valve.