Control Unit
- Check condition of 5-amp fuse, which is located under terminal connectors.
- Referring to Fig. 1. for terminal locations, check that current flows to terminals "B", "J", "R" and "O" when engine is operating at idle. Voltage of about 3-8 volts should flow to terminal "A" when engine is operating at idle.
- Connect negative probe of voltmeter to terminal "P" and positive probe to other terminals as described below and check that 12 volts exist under conditions described:NOTE: On models with automatic transmission, place transmission in "PARK". Also disconnect electrical coupler from throttle sensor on carburetor and connect a known good throttle sensor to coupler.
- At terminal "D" at any engine operating condition.
- At terminal "E" voltage should be 7.7-8.5 volts at any engine operating condition.
- At terminal "F" with decreasing engine speed more than 1000-1200 RPM with choke knob fully pushed in (throttle sensor rod fully extends).
- At terminal "L" with decreasing engine speed less than 1000-1200 RPM.
- At terminal "N" when applying battery power to terminal "U" with engine operating.
- At terminal "N" with decreasing engine speed more than 3600-4400 RPM (throttle sensor rod fully extends).
- At terminal "N" with decreasing engine speed more than 1000-1200 RPM with No. 2 water temperature switch (on radiator) disconnected (throttle sensor rod fully extended).
- At terminal "Q" (manual transmission) with engine operating and throttle sensor rod fully extended.
- At terminal "Q" (manual transmission) with decreasing engine speed less than 1000-1200 RPM when throttle sensor rod is fully pushed in.
- At terminal "Q" (automatic transmission) at any engine operating condition.
- At terminal "Q" (automatic transmission) with engine operating when throttle sensor coupler (Green/Black wire) is disconnected (throttle sensor rod fully extended).
- At terminal "Q" (automatic transmission) with decreasing engine speed less than 1000-1200 RPM when starting motor magnetic switch coupler (Black/Yellow wire) is disconnected and throttle sensor rod is fully pushed in.
- At terminal "S" (except Calif. manual transmission) with engine operating and battery power applied to terminal "C" or terminal "J".
- At terminal "S" (except Calif. manual transmission) with engine operating and throttle sensor rod fully pushed in.
- At terminal "S" (except Calif. manual transmission) with decreasing engine speed less than 1000-1200 RPM.
- At terminal "U" with engine operating and heat hazard sensor electrical coupler disconnected.NOTE: On models with automatic transmission, current should stop flowing to terminal "S" when starting motor magnetic switch coupler (Black/Yellow wire) is disconnected.