Rear HO2S heater resistance inspection

WARNING: This page is about a different variant/trim than selected.

Disconnect the rear HO2S connector.
Measure the rear HO2S resistance between terminals C and D.
- If not within the specification, replace the HO2S.
Rear HO2S heater resistance

2-50 ohms

Fig 1: Identifying Rear HO2S Wiring Harness Side Connector Terminals
Courtesy of MAZDA MOTORS CORP.