Mazda CX-9 Grand Touring 2007 Manual page 328

Fig. 2: Identifying Ignition Coil And Connector With Torque Specifications
IGNITION COIL INSPECTION [MZI-3.5]
SECONDARY COIL RESISTANCE INSPECTION
1. Remove the ignition coils. (See IGNITION COIL REMOVAL/INSTALLATION [MZI-3.5].)
2. Using a tester, measure the resistance between the ignition coil terminal A and ignition coil boot socket.
If not within the specification, replace the ignition coil.
Ignition coil secondary coil resistance
5-6 kilohms
Fig. 3: Measuring Resistance Between Ignition Coil Terminal A And Ignition Coil Boot Socket
SPARK PLUG REMOVAL/INSTALLATION [MZI-3.5]
2007 Mazda CX-9 Grand Touring
2007 ENGINE PERFORMANCE Ignition System (MZI-3.5) - CX-9