Diagnostic Circuit Test
- With ECA connected, turn ignition on. Measure voltage from ECA connector J1 pin 11 to J1 pin 12. If voltage is 4-6 volts, proceed with test. If If voltage is not 4-6 volts, perform Reference Voltage Test.
- Turn ignition on and measure voltage from Blk/Wht wire in Self Test connector to battery negative post. If voltage is greater than 0.5 volts, perform Battery Voltage Test. If voltage is less than 0.5 volts, proceed with test.
- With ignition on and processor connected, measure voltage between battery positive post and ECA connector J2 pin 11, then between battery positive post and J2 pin 12. If either or both readings are greater than 0.5 volts, perform battery voltage test. If both readings are less than 0.5 volts, proceed with test.
- Turn ignition off and disconnect ECA connector J1. Check continuity from ECA connector J1 pin 13 to Wht/Red wire at Self Test Plug. If resistance is 5 ohms or more, repair open circuit. If resistance is less than 5 ohms, proceed with test.
- Turn ignition off and disconnect ECA connector J2. Check continuity from ECA connector J2 pin 18 to Tan/Red wire at Self Test Plug. If resistance is 5 ohms or more, repair open circuit. If resistance is less than 5 ohms, proceed with test.
- With ignition off and ECA disconnected, measure resistance between EGO ground point and ECA connector J1 pin 5. If resistance is more than 5 ohms, repair ground wire circuit. If resistance is 5 ohms or less, inspect ECA connectors for damaged or corroded terminals. Reconnect ECA and retest. If problem is still present, replace ECA.