P0455 on Toyota Grand Highlander: Fix & DLC Location
Factory diagnostic troubleshooting wire for fault code P0455 (P0455: Evaporative Emission Control System Leak Detected (Gross Leak)) specifically on the Toyota Grand Highlander (2024–2026, 2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD).
1. Symptoms of P0455 on Toyota Grand Highlander
When the Engine Control Module (ECM/PCM) on your Toyota Grand Highlander (2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD) logs fault code P0455, drivers commonly observe:
2. Most Likely Causes on Toyota Grand Highlander
Historical warranty claims and technical repair bulletins for Toyota Grand Highlander point to the following failure distribution:
3. Step-by-Step DIY Repair Guide for Toyota Grand Highlander
Remove gas cap, inspect rubber O-ring for cracks, tighten until it clicks 3 times. on the Toyota Grand Highlander equipped with 2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD.
If the cap rubber is dried or cracked, replace with genuine OEM cap ($15). on the Toyota Grand Highlander equipped with 2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD.
Disconnect electrical plug and vacuum hose. Apply 12V; verify valve seals tight when unpowered. on the Toyota Grand Highlander equipped with 2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD.
Check vent valve for road salt corrosion or spider nest clogs. on the Toyota Grand Highlander equipped with 2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD.
Pump mineral oil smoke into EVAP port to reveal any hairline cracked lines. on the Toyota Grand Highlander equipped with 2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD.
Other Common Fault Codes on Toyota Grand Highlander
Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Toyota Grand Highlander:
4. Toyota Grand Highlander P0455 FAQs
What causes code P0455 to trigger on a Toyota Grand Highlander?
On the Toyota Grand Highlander (2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD), P0455 is most frequently caused by Missing, loose, or cracked gas cap seal or Faulty EVAP purge control solenoid.
Where is the OBD-II port located on my Toyota Grand Highlander?
On the Toyota Grand Highlander, the 16-pin DLC diagnostic connector is located Driver side lower knee panel above dead pedal. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.
Can I safely drive my Toyota Grand Highlander with code P0455?
Yes. Completely safe to drive, but emissions test will fail. Given that P0455 carries a Low severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.