DTC P0115: ECT Sensor Circuit Malfunction

Engine Coolant Temperature (ECT) sensor circuit malfunction code may be set by:

• ECT sensor malfunction.
• Open or short circuit between PCM connector C254 terminal No. 4 and ECT sensor terminal No. 1.
• Open or short circuit between PCM connector C254 terminal No. 6 and ECT sensor terminal No. 2.

1. Check ECT sensor and PCM connections. Repair as needed. Go to next step.
2. Check PCM pin voltage at connector C254 terminal No. 4. See PIN VOLTAGE CHARTS article. If voltage is okay, go to step 6). If voltage is out of specification go to next step.
3. Disconnect ECT sensor. Turn ignition on. Check voltage at ECT sensor connector terminal No. 1. If 5 volts exists, go to next step. If 5 volts does not exist, repair short between PCM connector C254 terminal No. 4 and ECT sensor connector terminal No. 1.
4. Check continuity between PCM connector C254 terminal No. 8 and ECT sensor connector terminal No. 2. If continuity exists, go to next step. If continuity does not exist, repair or replace wiring.
5. Check ECT sensor. See ECT SENSOR in SYSTEM/COMPONENT TESTS article. If sensor is bad, replace sensor. If sensor is okay, go to next step.
6. Clear code. Recheck codes. If code returns, replace PCM. If code does not return, problem is intermittent.