System Testing
- Place vehicle on a chassis dynamometer or install a jumper wire from control box No. 2 (Green/White wire) to vehicle interior. Connect voltmeter positive probe to Green/White wire or jumper wire and negative probe to ground. Warm-up engine to normal operating temperature. Road test or run vehicle on dynamometer.
- There should be voltage while the vehicle is cruising at a constant 30 MPH in 3rd gear. If there is voltage at 30 MPH in 3rd gear, proceed to step 5). If there is no voltage at 30 MPH in 3rd gear, and/or there is voltage on acceleration, voltage while in 1st or 2nd gear, or voltage above 3000 RPM, check the following:
- Check signal to power valve control solenoid valve. Check vacuum switch B, clutch switch, speed sensor, thermosensor B and vacuum switch F. Check for voltage at control unit connector (Blue wire) with ignition on. There should be voltage. If no voltage, check Blue wire between control unit and ignition coil.
- Check for voltage at control unit connector (Black/Yellow wire) with ignition on. There should be voltage. If no voltage, check fuse and wiring. Ensure Black wire between control unit and ground has continuity.
- Stop engine and remove jumper wire. Disconnect vacuum hoses No. 2 and No. 5 from control box No. 2 at vacuum hose manifold. Connect a vacuum pump to each hose. Apply vacuum. There should be vacuum. If there is vacuum at both hoses, proceed to step 7).
- If there is no vacuum at hose No. 2, replace primary slow cut-off solenoid valve and retest. If there is no vacuum at hose No. 5, replace primary main air cut-off solenoid valve and retest.
- Apply voltage to primary air cut-off solenoid valves. There should be no vacuum. If there is no vacuum at either hose, test is complete. If there is vacuum at hose No. 2, replace primary slow air cut-off solenoid valve and retest. If there is vacuum at hose No. 5, replace primary main air cut-off solenoid valve and retest.