A P1115 trouble code is related to a high voltage reading from either the engine coolant temperature or intake air temperature sensor that relays temperatures to the engine computer.
What the P1115 code means
P1115 is a OBD-II manufacturer-specific code for a voltage issue with either the engine coolant temperature or intake air temperature sensor in that the signal being sent to the engine computer is higher than the manufacturer’s parameters. A high voltage reading is usually associated with lower engine coolant or air intake temperatures being read by gauges. This code is very similar to a P1114 with the exception of the voltage reading being high.
What causes the P1115 code?
The most common causes for a P1115 are:
- Faulty intake air temperature sensor
- Faulty intake air temperature sensor wiring/electrical connectors
- Faulty engine coolant temperature sensor
- Faulty engine coolant temperature sensor wiring/electrical connectors
- Faulty engine computer computer
What are the symptoms of the P1115 code?
Some of the symptoms of bad intake air temperature sensors range from a lack of power, trouble with cold starts, and decreased fuel economy. A faulty engine coolant temperature sensor will usually only result in a higher than actual temperature reading, or an inoperable temperature gauge all together.
How does a mechanic diagnose the P1115 code?
The cause of a P1115 code will not only depend on what the code reads, but what make your vehicle is as they are manufacturer specific. Some codes may point directly at the engine temperature sensor being the fault, requiring your mechanic conducts both a visually inspection and monitor of the signal being sent out by the sensor. Testing for a intake air temperature sensor will be similar and with a P1115, your mechanic will need to look for a higher signal being sent by the sensors.
If the readings of any sensor is not within the manufacturer’s parameters, they will need to be replaced.
Common mistakes when diagnosing the P1115 code
Because all P1XXX codes are manufacturer specific, it’s critical to have any code read by a professional-grade OBD-II scanner to ensure you’re fixing the correct problem. This is even more prevalent with P1115 codes as each manufacturer will require different repair techniques. For example, Mazda specific codes require troubleshooting of the intake air temperature sensors while Honda’s deal with the engine coolant temperature sensor.
How serious is the P1115 code?
Faulty intake air temperature readings can cause a variety of unsavory driving characteristics, making it fairly serious for you to correct a P1115 as quickly as possible. Codes relating to an engine coolant temperature sensor may be even more important as they’ll typically read higher coolant readings than what is actually circulating through the engine.
What repairs can fix the P1115 code?
The most common repairs for a P1115 are as follows:
- Replacing the engine coolant temperature sensor
- Replacing the intake air temperature sensor
- Repairing and cleaning intake air temperature sensor wiring
- Repairing and cleaning engine coolant temperature sensor wiring
- Replacing the engine computer
Additional comments for consideration regarding the P1115 code
All P1115 codes can be found on Volkswagen/Audi, Ford, Isuzu, Mazda, Honda/Acura, General Motors, and Ford vehicles.
Need help with a P1115 code?
YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.