Mazda CX-9 Grand Touring 2007 Manual page 169

Fig. 25: Identifying HO2S Sensor Connector Terminals
Courtesy of MAZDA MOTORS CORP.
CIRCUIT OPEN/SHORT INSPECTION
1. Disconnect the PCM connector. (See PCM REMOVAL/INSTALLATION [MZI-3.5].)
2. Inspect the following wiring harness for open or short (continuity check).
2007 Mazda CX-9 Grand Touring
2007 ENGINE PERFORMANCE Control System (MZI-3.5) - CX-9