Component Inspection

Engine

Engine Control - P0031 HO2S Heater Circuit Low (Sensor1) - Component Inspection

Component Inspection

1. Check resistance
(1) IG "OFF".
(2) Disconnect HO2S (S1) connector.
(3) Measure resistance between terminal 3 and 4 of HO2S (S1)(Component Side)
A. Specification :









(4) Is the measured resistance within specification?
YES
1) Substitute with a known - good ECM and check for proper operation.
If the problem is corrected, replace ECM and go to "Verification of Vehicle Repair" procedure.
NO
1) Substitute with a known - good HO2S (S1) and check for proper operation.
If the problem is corrected, replace HO2S (S1) and go to "Verification of Vehicle Repair" procedure.