Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is getting confusing information from the sensor that tells it how hot or cold the air outside is. It's like the car is trying to read the weather, but the thermometer is broken.
The engine control module (ECM) is receiving an incorrect or implausible signal from the ambient air temperature sensor.
The P1115 code indicates that the ECM has detected a problem with the ambient air temperature sensor's signal. This sensor helps the ECM adjust various engine parameters based on the outside air temperature. If the signal is erratic or out of expected range, it triggers this code.
• Check Engine Light is on
• Poor fuel economy
• Engine performance issues
• Faulty ambient air temperature sensor
• Damaged wiring or connectors
• Faulty ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the ambient air temperature sensor and its wiring.
• Test the sensor with a multimeter for proper resistance.
• Replace the ambient air temperature sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $300
Moderate
• BMW 3 Series (E36)
• BMW 5 Series (E39)
• BMW Z3
• Regularly inspect sensor connections.
• Keep the sensor clean and free from debris.
• Perform routine vehicle diagnostics.
Sensor Issue
• Have your vehicle inspected by a professional.
• Avoid ignoring the Check Engine Light.
• Regular maintenance can prevent sensor issues.
Check with your vehicle manufacturer for specific warranty coverage related to sensors.
This code has been associated with BMW vehicles due to sensor and wiring issues, particularly in models from the late 1990s to early 2000s.
Moderate – Addressing this issue can prevent further engine performance problems.
Driving with a malfunctioning sensor can lead to increased emissions and potential engine damage.
• Vehicle must be at operating temperature.
• Ensure the ambient air temperature is stable.
The ambient air temperature sensor is usually located near the front of the vehicle, often behind the front bumper or grille.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to poor fuel economy and potential engine performance issues.
Q: Can I drive with this code?
A: While you can drive with this code, it's best to address it soon to avoid further issues.
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