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Home >> Isuzu >> 1992 >> Impulse RS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Code Charts >> Code 45 (1.6L SOHC) - O2 Sensor Rich Fuel Mixture (Non-Heated Sensor) >> Notes
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Code 45 (1.6L SOHC) - O2 Sensor Rich Fuel Mixture (Non-Heated Sensor): Notes

The ECM supplies a voltage of approximately .43 volt between ECM terminals D6 and D7 (if measurement is taken with a 10-megohm DVOM, reading may be as low as .32 volt). The O2 sensor varies voltage from .1 volt (lean exhaust) to 1 volt (rich exhaust). When sensor temperature is less than 600°F (316°C), the sensor acts like an open circuit and will not produce voltage. An open sensor circuit or cold sensor will cause an open loop condition.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. Code 45 will set when sensor voltage signal is greater than .75 volt under following conditions:
    • temperature is greater than 157°F (69.5°C).
    • Integrator count is not at 128.
    • No Code 21A, 21B, 33A or 33B is set.
    • TPS is greater than 10 percent (A/T) or 8 percent (M/T).
    • System is in closed loop.