P1115: Engine Coolant Temperature (ECT) Sensor Circuit Intermittent High Voltage IAT - B Circuit High Input
Methodology: We combine code standards with complaint and reliability patterns, then review for clear, vehicle-first diagnosis steps.
Sources: SAE/OBD-II definitions, manufacturer service information, and public reliability reports (including NHTSA where applicable).
Limits: Guidance is informational and may not match every model-year or revision. Confirm with the official manual and diagnostics before replacing parts. For safety-critical or electrical work, use a qualified technician.
What Does P1115 Mean?
P1115 is a manufacturer-specific diagnostic trouble code: Engine Coolant Temperature (ECT) Sensor Circuit Intermittent High Voltage IAT - B Circuit High Input. This code applies to FORD, OTHER, LINCOLN, MERCURY, OLDSMOBILE vehicles. Unlike generic OBD-II codes, manufacturer-specific codes are defined by the vehicle maker and may only apply to certain makes and models.
Symptoms of P1115
- β οΈ Check Engine Light (MIL) illuminated
- β οΈ Engine Coolant Temperature (ECT) Sensor Circuit Intermittent High Voltage IAT - B reading stuck at maximum value
- β οΈ Related system operating erratically or in default mode
- β οΈ Reduced engine performance
Common Causes
- π Short to voltage in Engine Coolant Temperature (ECT) Sensor Circuit Intermittent High Voltage IAT - B wiring harness
- π Corroded or water-damaged Engine Coolant Temperature (ECT) Sensor Circuit Intermittent High Voltage IAT - B connector
- π Faulty Engine Coolant Temperature (ECT) Sensor Circuit Intermittent High Voltage IAT - B outputting maximum voltage
- π Damaged wiring rubbing against metal components
- π ECM/PCM internal fault (rare)
Frequently Asked Questions
What does P1115 mean?
Can I drive with code P1115?
How much does it cost to fix P1115?
What To Do Next
Possible Fixes
- π§ Inspect and repair Engine Coolant Temperature (ECT) Sensor Circuit Intermittent High Voltage IAT - B wiring for short to voltage
- π§ Clean or replace corroded Engine Coolant Temperature (ECT) Sensor Circuit Intermittent High Voltage IAT - B connector
- π§ Replace faulty Engine Coolant Temperature (ECT) Sensor Circuit Intermittent High Voltage IAT - B
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