COMPONENT TESTING

Three-Way Solenoid Valve

1. Disconnect the vacuum sensing tube A from the servo diaphragm.
2. Disconnect the vacuum sensing tube B from the three-way solenoid valve.

   Fig. 1: Three-way solenoid valve check with the ignition switch ON

   Fig. 2: Three-way solenoid valve check with the ignition switch OFF

3. Detach the connector (blue/black wire) from the engine speed switch and ground the three-way solenoid valve using a jumper wire.
4. Turn the ignition switch ON.
5. Blow into the three-way solenoid valve through tube A and make sure air comes out of the valve's filter.
6. Turn the ignition switch OFF.
7. Blow into the valve through tube A and make sure air comes out of port A.
8. Replace the three-way solenoid valve if it does not operate properly.

Engine Speed Switch

1. Detach the engine speed switch connector.
2. Attach a voltmeter to the connector.

   Fig. 3: Engine speed switch check

3. Increase the engine speed to 2,000 rpm, then slowly decrease the engine speed.
4. Record the engine speed at which the current flows to the circuit. The engine speed should be 1,600–1,800 rpm (California AT) and 1,400–1,600 rpm (Canada MT).
5. Slowly increase the engine speed again and record the engine speed at which the current does not flow to the circuit. The difference between the engine speed recorded in steps 4 and 5 should be 150–250 rpm.
6. Replace the engine speed switch if the rpm specifications are not met.