HO2S circuit open/short inspection (heater): Notes

WARNING: This page is about a different car, the 2005 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect the PCM connector.
Inspect the following wiring harnesses for an open or short circuit. (Continuity inspection)

Fig 1: Identifying Connector
Courtesy of MAZDA MOTORS CORP.

Fig 2: Identifying PCM Harness Side Connector
Courtesy of MAZDA MOTORS CORP.