P0304 on Lexus RX: Fix & DLC Location
Factory diagnostic troubleshooting wire for fault code P0304 (P0304: Cylinder 4 Misfire Detected) specifically on the Lexus RX (2020–2026, 2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP)).
1. Symptoms of P0304 on Lexus RX
When the Engine Control Module (ECM/PCM) on your Lexus RX (2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP)) logs fault code P0304, drivers commonly observe:
2. Most Likely Causes on Lexus RX
Historical warranty claims and technical repair bulletins for Lexus RX point to the following failure distribution:
3. Step-by-Step DIY Repair Guide for Lexus RX
Interface with the diagnostic port or system console using verified scanning hardware. Record freeze-frame data, active sub-codes, and timestamps to isolate whether P0304 is static or intermittent. on the Lexus RX equipped with 2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP).
Visually inspect the physical component (Cylinder 4 Spark Plug / Wiring), connector pins, and associated wiring harnesses for signs of corrosion, thermal melting, or loose grounding clips. on the Lexus RX equipped with 2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP).
Measure reference voltages and resistance thresholds against manufacturer factory specifications. Replace any component failing nominal impedance tolerances. on the Lexus RX equipped with 2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP).
Install genuine OEM replacement hardware or execute registry / service commands. Ensure all mounting bolts are torqued to factory specifications. on the Lexus RX equipped with 2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP).
Erase the fault code from non-volatile memory. Perform a standard verification cycle (e.g. 15-minute mixed drive or system stress benchmark) to ensure monitors reset to 'Ready' state without recurrent fault flags. on the Lexus RX equipped with 2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP).
Other Common Fault Codes on Lexus RX
Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Lexus RX:
4. Lexus RX P0304 FAQs
What causes code P0304 to trigger on a Lexus RX?
On the Lexus RX (2.4L Turbo (RX 350 275HP) / 2.5L Hybrid / 2.4L Turbo Performance Hybrid (RX 500h 366HP)), P0304 is most frequently caused by Component aging, oxidation, or degraded internal circuit element (Cylinder 4 Spark Plug / Wiring) or Wiring harness abrasion, loose terminal pin, or ground voltage float.
Where is the OBD-II port located on my Lexus RX?
On the Lexus RX, the 16-pin DLC diagnostic connector is located Driver footwell above brake pedal assembly. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.
Can I safely drive my Lexus RX with code P0304?
No. Immediate shutdown / repair required to prevent permanent hardware destruction or total system lockup. Given that P0304 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.