System Diagnosis - California

Chart C-6:

Wiring Diagram for Chart C-6:

CIRCUIT DESCRIPTION:

The Electric Diverter Valve (EDV) uses a solenoid to direct air into the exhaust ports, or to atmosphere. During cold engine starts, the ECM completes the ground circuit and the EDV solenoid is energized. Air is directed into the exhaust ports whenever the engine is started. When the vehicle is operating in "Closed Loop," or at wide open throttle, the ECM opens the circuit. This allows air to be directed to atmosphere through the divert silencer.


TEST DESCRIPTION: The numbers below refer to circled numbers on the diagnostic chart.

1. If the EDV does not have 10 inches of Hg (34 kPa) of vacuum applied to the valve, inspect for pinched, plugged, or a leak in the vacuum hose. Since this is a system performance test, the vehicle will go into "Closed Loop" operation, and air will be diverted from the exhaust ports to atmosphere.
2. This test checks for a grounded Electric Divert Valve (EDV) circuit. Normally, the system light will be OFF.
3. This checks for a open circuit. Grounding the diagnostic test terminal will energize the solenoid if the ECM and/or circuit is okay. If the test light is ON, the circuit is okay, and the fault is in the valve or valve connections.

NOTE: Once the test sequence is completed, clear codes and verify NO "Service Engine Soon" light exists.



DIAGNOSTIC AIDS:

This California equipped vehicle uses the same wiring harness as the Federal vehicle, but the A.I.R. Converter solenoid connector is not used. The connector is taped to the harness.