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Home >> Ford >> 1990 >> Bronco II 4WD, Standard, M5OD-R1 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Test H - Fuel Control >> Test H: Step 23
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Test H: Step 23

23) Code 42 or 92: Fuel Control Always Rich, Check HEGO SIGNAL For Short To Power  On dual HEGO systems, Code 42 refers to right (or rear) side HEGO, Code 92 refers to left (or front) side HEGO. Turn key off and wait 10 seconds. Disconnect appropriate HEGO sensor. Set DVOM on 20-volt scale. With KOEO, measure voltage between HEGO SIG and PWR GND at HEGO vehicle harness connector. If reading is more than .5 volt, repair short to power in HEGO circuit. Reconnect HEGO sensor and repeat QUICK TEST. If reading is less than 0.5 volt, go to next step.

Fig 1: HEGO Sensor Connector
G90C12445