LEMON Manuals: Even more car manuals for everyone
Home >> Mazda >> 2002 >> Tribute LX, 4WD >> Repair and Diagnosis >> External Pages >> Different car >> Section 5 (Engine Controls - Tests W/Codes - 2.3L) >> Circuit Tests >> DTC P0115 - Engine Coolant Temperature (ECT) Sensor Circuit Malfunction >> Diagnosis & Repair Procedure

Diagnosis & Repair Procedure

WARNING: This page is about a different car, the 1997 Mazda Millenia. However, it is still accessible from the selected car via links, so may be relevant.
  1. Inspect all applicable harness connectors. Repair as needed. Turn ignition on. Access ECM harness connector. ECM is mounted in front of center console, under radio. Using voltmeter, backprobe applicable ECM harness connector. Measure voltage between ground and terminal No. 3Q.
  2. Voltage should be 3.0-3.1 volts with coolant temperature of 68° F (20° C), and .8 volt with engine at normal operating temperature. If voltage is within specification, go to step 5). If voltage is not within specification, go to next step.
  3. Turn ignition off. Disconnect ECT sensor connector. Turn ignition on. Measure voltage between ground and terminal "A" (Red/Green wire) on harness connector. If 5 volts is present, go to next step. If 5 volts is not present, check for open or short circuit between ECT sensor and ECM. Repair as needed.
  4. Check continuity of Black/Yellow wire between terminal "B" on ECT sensor harness connector and terminal No. 3AB on ECM harness connector. Repair as needed. If continuity exists, go to next step.
  5. Inspect ECT sensor. See appropriate SYSTEM/COMPONENT TESTS - 2.3L article. Replace as needed. If ECT sensor is okay, go to next step.
  6. Erase DTCs. See CLEARING CODES  in SELF-DIAGNOSTIC SYSTEM section. If DTC resets, replace ECM. If DTC is not present, intermittent poor harness connection may have caused DTC to originally set.
scientia non olet · About LEMON Manuals