Circuit Open/Short Inspection

Disconnect the PCM connector. (See PCM REMOVAL/INSTALLATION .)
Inspect the following wiring harnesses for open or short circuit (continuity check).
1. Open Circuit
  - If there is no continuity, there is an open circuit. Repair or replace the wiring harness.
    - Fuel injector No. 1 terminal A and PCM terminal 2BB
    - Fuel injector No. 2 terminal A and PCM terminal 2BC
    - Fuel injector No. 3 terminal A and PCM terminal 2BD
    - Fuel injector No. 4 terminal A and PCM terminal 2AZ
    - Fuel injector No. 1 terminal B and main relay terminal B
    - Fuel injector No. 2 terminal B and main relay terminal B
    - Fuel injector No. 3 terminal B and main relay terminal B
    - Fuel injector No. 4 terminal B and main relay terminal B
1. Short circuit
  - If there is continuity, there is a short circuit. Repair or replace the wiring harness.
    - Fuel injector No. 1 terminal A and body GND
    - Fuel injector No. 2 terminal A and body GND
    - Fuel injector No. 3 terminal A and body GND
    - Fuel injector No. 4 terminal A and body GND
Fig 1: Identifying Fuel Injector & PCM Wiring Harness Side Connector Terminals
Courtesy of MAZDA MOTORS CORP.