Vacuum Diagnosis - With Electronic A/C

To avoid misdiagnosis, perform CHART #1 before beginning Vacuum Diagnosis.

1. Check vacuum supply to Solenoid Module (black vacuum hose) while engine is running.
^ Vacuum should be approximately 60 kPa (18 psi) with engine running.
^ Vacuum should remain at approximately 60 kPa (18 psi) when engine is turned off.
2. Test each vacuum actuator by disconnecting the vacuum hose and applying vacuum directly to the actuator. Repair or replace as necessary.

Fig. 1 Air Delivery Vacuum Distribution Table:

3. Reconnect all vacuum and electrical connections. Run engine and cycle through the operating modes of the Electronic A/C Control Assembly while observing the vacuum actuators.
^ Check for vacuum to the vacuum actuators by noting vacuum actuator position. When vacuum is applied, the actuator will retract, refer to Fig. 1.
^ If a vacuum actuator retracts when it should not, replace the Electronic A/C Control Assembly.
^ If a vacuum actuator does not retract when it should, check for vacuum leaks, collapsed vacuum hoses, binding valves or bad connections at the Solenoid Module. If OK, replace the Solenoid Module.