Parts for your 2015 Isuzu D-max-Throttle position sensors

2015 Isuzu D‑MAX throttle position sensors — are they actually used?

For the 2015 Isuzu D‑MAX (3.0‑litre 4JJ1 diesel), a conventional, standalone throttle position sensor (TPS) like you’d see on a petrol engine isn’t used. Instead, the engine management relies on an accelerator pedal position (APP) sensor at the pedal and an electronically controlled intake throttle valve (for EGR flow and smooth shutdown), which has its own built‑in position feedback. There’s no separate, serviceable TPS mounted on a cable‑driven throttle body, because the diesel doesn’t meter engine load by throttling air.

This design is confirmed by Isuzu’s technical literature for the 4JJ1 engine, which describes an “accelerator pedal position sensor (dual‑track)” and an “electronic throttle/intake shutter with integrated position sensing,” rather than a replaceable TPS. Diagnostic information for the platform also maps OBD codes like P0120–P0124 to “Throttle/Pedal Position” circuits, which in practice refer to the pedal sensor or the intake throttle actuator feedback, not a standalone TPS unit.

Why it isn’t used: diesels regulate torque with fuel quantity, not by choking airflow. The intake throttle in the D‑MAX is there mainly to assist EGR and to stop the engine cleanly at key‑off. Because of that, there’s no separate TPS to service. If there’s a “throttle sensor” fault on a 2015 D‑MAX, workshops typically diagnose either the accelerator pedal assembly (APP sensor) or the intake throttle body assembly (motor plus internal position sensor).

What owners and techs should look after instead:

• Keep the intake throttle/EGR area clean. Carbon build‑up can stick the throttle plate and upset the position feedback.
• Check wiring and connectors at the pedal and intake throttle body for corrosion, moisture, or rub‑through.
• Use a scan tool to check live data: APP sensor tracks (two signals that rise smoothly together) and the intake throttle commanded vs. actual position.
• If the intake throttle’s sensor fails, replace the complete throttle body assembly, the sensor isn’t generally sold separately.
• After replacing the pedal or throttle body, follow the service manual’s learn or reset procedures via a scan tool if required.

Technical references: Isuzu D‑MAX 2012–2016 Workshop Manual (Engine Control System, 4JJ1), Isuzu 4JJ1 engine training materials on accelerator pedal and intake throttle control, and Denso common‑rail diesel system guides outlining diesel torque control by fuel with intake throttles used for EGR/shutdown. OBD‑II documentation for the platform maps “Throttle/Pedal Position” DTCs to APP or electronic intake throttle circuits rather than a standalone TPS.

Does a 2015 D‑MAX have a throttle position sensor?

No separate TPS. It uses a dual‑track accelerator pedal position sensor and an electronic intake throttle with a built‑in position sensor. Any “TPS” fault on a scan tool usually points to one of these two assemblies, not a standalone sensor on a throttle shaft.

If there’s a throttle sensor fault, what gets replaced?

Generally the complete accelerator pedal assembly (if the APP sensor is faulty) or the entire intake throttle body (if its internal motor/position sensor has failed). The position sensor isn’t normally a separate spare on the diesel throttle body.

What maintenance helps prevent throttle/position issues on a 2015 D‑MAX?

Periodic cleaning of the intake throttle and EGR passages, checking harness plugs for oil or moisture, and scanning live data to confirm smooth APP tracks and correct intake throttle movement. After parts replacement, perform any required learns or resets with a proper scan tool.