Safety Warning

DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.

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HOMESERVICE MANUALSMAZDA20086 S SPORT, 4D HATCHBACK, STANDARDREPAIR AND DIAGNOSISENGINE PERFORMANCETESTING & DIAGNOSISON-BOARD DIAGNOSTIC [ENGINE CONTROL SYSTEM (AJ]DTC P0505 [AJ]NOTES

2008 Mazda 6 s Sport, 4D Hatchback, Standard

DTC P0505 [AJ]: Notes

2008 Mazda 6 s Sport, 4D Hatchback, StandardSECTION Notes

DTC P0505 [AJ] DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0505	Idle control system malfunction
DETECTION CONDITION	The PCM cannot control idle speed at the target idle speed during the KOER self test.
POSSIBLE CAUSE	Electronic throttle control system malfunction Air cleaner element clogged Air intake passage clogged A/C relay control circuit malfunction Generator control circuit malfunction Low engine compression (Over capacity of blow-by gas) PCM malfunction

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.
• Brakes feel soft, pull hard to one side, or make grinding noises.
• The engine overheats, stalls repeatedly, or misfires under load.
• You are missing required tools, torque specs, or safe lifting equipment.
• You are not confident in the next step or safety outcome.