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Home >> Mazda >> 2012 >> CX-9 FWD V6-3.7L >> Repair and Diagnosis >> Powertrain Management >> Fuel Delivery and Air Induction >> Fuel Injector >> Testing and Inspection
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Fuel Injector: Testing and Inspection





FUEL INJECTOR INSPECTION [MZI-3.7]

Resistance Inspection

1. Turn the ignition switch to LOCK position.

2. Disconnect the negative battery cable. Removal and Replacement

3. Remove the engine cover. Engine Cover Removal/Installation

4. Remove the dynamic chamber. Service and Repair

5. Disconnect the fuel injector connectors.

6. Measure the resistance of the fuel injector.






Fuel injector resistance
- 11.3-12.7 ohms

- If not as specified, replace the fuel injector. Service and Repair
- If as specified, carry out the "Circuit Open/Short Inspection".

Circuit Open/Short Inspection

1. Disconnect the PCM connector.

2. Inspect the following wiring harness for open or short (continuity check).













Open circuit

- If there is no continuity, the circuit is open. Repair or replace the harness.

- No.1 cylinder fuel injector terminal A and PCM terminal 2BQ
- No.2 cylinder fuel injector terminal A and PCM terminal 2BC
- No.3 cylinder fuel injector terminal A and PCM terminal 2AY
- No.4 cylinder fuel injector terminal A and PCM terminal 2BG
- No.5 cylinder fuel injector terminal A and PCM terminal 2BL
- No.6 cylinder fuel injector terminal A and PCM terminal 2BI
- No.1 cylinder fuel injector terminal B and fuel pump relay terminal D
- No.2 cylinder fuel injector terminal B and fuel pump relay terminal D
- No.3 cylinder fuel injector terminal B and fuel pump relay terminal D
- No.4 cylinder fuel injector terminal B and fuel pump relay terminal D
- No.5 cylinder fuel injector terminal B and fuel pump relay terminal D
- No.6 cylinder fuel injector terminal B and fuel pump relay terminal D

Short circuit

- If there is continuity, the circuit is short. Repair or replace the harness.

- No.1 cylinder fuel injector terminal A and body ground
- No.2 cylinder fuel injector terminal A and body ground
- No.3 cylinder fuel injector terminal A and body ground
- No.4 cylinder fuel injector terminal A and body ground
- No.5 cylinder fuel injector terminal A and body ground
- No.6 cylinder fuel injector terminal A and body ground
- No.1 cylinder fuel injector terminal B and power supply
- No.2 cylinder fuel injector terminal B and power supply
- No.3 cylinder fuel injector terminal B and power supply
- No.4 cylinder fuel injector terminal B and power supply
- No.5 cylinder fuel injector terminal B and power supply
- No.6 cylinder fuel injector terminal B and power supply

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