Parts for your 2012 Mazda Cx-5-Throttle position sensors

2012 Mazda CX-5 Throttle Position Sensor (TPS)

Based on Mazda’s own workshop documentation for the 2012 CX-5 (SKYACTIV-G 2.0 and SKYACTIV-D 2.2), the vehicle uses an electronic throttle body that contains dual throttle position sensors (often listed as TP No.1 and TP No.2) along with a throttle actuator. Mazda service information and DTC charts also reference TPS-related fault codes (e.g., P0121–P0123, P2135), confirming the TPS is fitted and monitored by the PCM.

On a 2012 Mazda CX-5, the throttle position sensor tells the engine computer exactly how far the throttle plate is opened. That real-time signal lets the PCM balance air, fuel and spark, keep idle stable, sharpen throttle response and manage the auto’s shift strategy. The petrol CX-5 relies on the TPS for smooth acceleration and cruise control behaviour, while the diesel also uses throttle control to assist EGR flow and clean shutdowns. Because it’s a drive-by-wire setup, the TPS is built into the throttle body and works in tandem with the accelerator pedal position (APP) sensor for redundancy and safety.

There’s no routine replacement interval for the TPS on these Mazdas, but a bit of preventative care goes a long way. Keeping the throttle body clean, checking the harness for rub-through, and making sure the connector pins are clean and tight helps avoid gremlins. If the CX-5 shows symptoms like erratic idle, flat spots on take-off, surging, limited power (limp mode) or a glowing MIL with codes such as P0121, P0122, P0123 or P2135, it’s time for proper diagnosis.

• Scan live data to compare TP1/TP2 and APP correlations. Out-of-track signals or mismatched voltages point to trouble.
• Inspect wiring and grounds first, many “sensor” faults are actually connectivity issues.
• If the TPS has failed, the throttle body is typically replaced as an assembly. Use a new gasket and correct torque.
• Perform an electronic throttle/idle learn with a suitable scan tool after refit. The PCM may auto-learn, but a guided procedure is best practice.

In Aussie and Kiwi conditions—dust, heat, and plenty of stop–start—periodic intake cleaning and connector checks during routine servicing help keep the TPS happy. When in doubt, a workshop with Mazda IDS or an equivalent capable scan tool can confirm a diagnosis quickly and reset adaptations after repair.

Popular questions

Does the 2012 CX-5 have a separate TPS, or is it built into the throttle body?

It’s integrated. Mazda uses an electronic throttle body with twin TPS tracks inside the unit. If the sensor fails, the usual fix is replacing the complete throttle body rather than a standalone sensor.

What fault codes point to a bad TPS on a 2012 CX-5?

Common ones include P0121 (range/performance), P0122 (low), P0123 (high) and P2135 (throttle/pedal correlation). You might also see throttle actuator or idle control-related codes if the issue affects the whole assembly.

Do I need to do a relearn after replacing the throttle body?

Yes. An electronic throttle/idle learn is recommended. Some CX-5s will auto-learn with a short idle and drive cycle, but using a proper scan tool procedure delivers the quickest, most reliable result.