TPMS Sensor Frequency Mismatch
2000-2012 Mitsubishi Eclipse 2.4L I4 🇩🇪
Description
One or more TPMS sensors are transmitting on a different frequency than the vehicle receiver expects.
Symptoms
- TPMS warning light on
- Some sensors not reading
- New sensor not recognized
Common Causes
- Aftermarket sensor with wrong frequency
- European/Asian frequency sensor on US vehicle
- Mixed sensor brands
- Incorrect replacement sensor part number
Diagnostic Steps
- Verify sensor frequency with TPMS tool
- Check sensor part number compatibility
- Compare sensor frequency to vehicle specification
- Test each sensor individually
Repair Notes
Replace mismatched sensors with correct frequency sensors. US vehicles typically use 315 MHz, European/Asian use 433 MHz.
Related Codes
Other Body Codes
- B0001Driver Frontal Stage 1 Deployment Control
- B0002Driver Frontal Stage 2 Deployment Control
- B0003Passenger Frontal Stage 1 Deployment Control
- B0004Passenger Frontal Stage 2 Deployment Control
- B0005Driver Knee Airbag Deployment Circuit
- B0006Passenger Knee Airbag Deployment Circuit
- B0007Rear Left Side Airbag Deployment Circuit
- B0008Rear Right Side Airbag Deployment Circuit
- B0010Driver Side Airbag Deployment
- B0011Driver Side Airbag Deployment Circuit Open
B1021 on Other Vehicles
Mitsubishi Colt JP
2002-2012 1.3L I4 4A90
Mitsubishi Colt JP
2002-2012 1.5L I4 4A91
Mitsubishi Delica D:5
2019-2025 2.2L I4 Turbo Diesel 4N14
Mitsubishi Eclipse
2006-2012 2.4L I4
Mitsubishi Eclipse
2006-2012 3.8L V6
Mitsubishi Eclipse Cross
2018-2024 1.5L I4 Turbo
Mitsubishi Eclipse Cross
2018-2024 1.5L Turbo I4
Mitsubishi Eclipse Cross PHEV
2022-2024 2.4L I4 PHEV
Common Questions
What does code B1021 mean on a 2000-2012 Mitsubishi Eclipse?
B1021 stands for "TPMS Sensor Frequency Mismatch". One or more TPMS sensors are transmitting on a different frequency than the vehicle receiver expects.
What are the symptoms of B1021 on a Mitsubishi Eclipse?
Common symptoms of B1021 include: TPMS warning light on, Some sensors not reading, New sensor not recognized.
What causes B1021 on a 2000-2012 Mitsubishi Eclipse?
Common causes of B1021 include: Aftermarket sensor with wrong frequency, European/Asian frequency sensor on US vehicle, Mixed sensor brands, Incorrect replacement sensor part number.