Circuit Open/Short Inspection

Fig 1: Identifying ECT Sensor Harness-Side Connector Terminals

Courtesy of MAZDA MOTORS CORP.

1. Disconnect the PCM connector. (See PCM REMOVAL/INSTALLATION ).
2. Inspect the following wiring harnesses for an open or short circuit. (Continuity inspection)
   Fig 2: Identifying PCM Wiring Harness-Side Connector Terminals

   Courtesy of MAZDA MOTORS CORP.

Open circuit 

• If there is no continuity, there is an open circuit. Repair or replace the wiring harness.
  • ECT sensor terminal A and PCM terminal 2AH
  • ECT sensor terminal B and PCM terminal 2AY

Short circuit 

• If there is continuity, there is a short circuit. Repair or replace the wiring harness.
  • ECT sensor terminal A and power supply
  • ECT sensor terminal A and body ground
  • ECT sensor terminal B and power supply