Checking Speed and Idle Signal For Idle Control Unit

1. SPEED SIGNAL

a. Connect voltmeter between terminals 3 and 4. With ignition on, battery voltage should be present.
b. If no voltage is present, check for continuity (0 Ohms) between terminal 3 and socket 13 of the diagnosis socket. Repair open circuit as necessary.
c. If voltage is present, speed signal is OK.

2. IDLE SIGNAL

a. Connect voltmeter between terminals 4 and 12. With ignition on, battery voltage should be present momentarily.
b. If voltage is present, open throttle part way and check to see if voltage drops to 0 VDC. If not, adjust throttle cable or switch as necessary.
c. If voltage is not present, pull off multiple-pin plug on throttle switch. Connect voltmeter to center pin of the plug receptacle and ground. With ignition on, battery voltage should be present momentarily.
1. If not, repair power supply wiring as necessary.
2. If voltage is present, adjust throttle cable or switch as necessary.