APC System Test

Fig. 5 APC system troubleshooting chart (Part 1 of 3):

Fig. 5 APC system troubleshooting chart (Part 2 of 3):

�f�!Fig. 5 APC system troubleshooting chart (Part 3 of 3):

1. Disconnect hose to pressure transducer at manifold and plug manifold fitting.
2. Using a ``T'' connector, connect pressure gauge No. 8393514 or equivalent and a suitable pressure pump to the hose from the pressure switch.
3. Start engine and run at fast idle until it reaches normal operating temperature, then set engine to run at 2000 RPM.
4. Apply 6.6 psi (0.50 bar) pressure to pressure transducer and observe system operation.
5. Solenoid valve should begin to operate, identified by a ``chattering'' sound.
6. If solenoid valve does not operate, refer to troubleshooting chart, Fig. 5.
7. Release pressure and return engine to curb idle speed. Solenoid should not operate.
8. If solenoid continues to operate, refer to troubleshooting chart, Fig. 5.