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P0686 — ECM/PCM Power Relay Control Circuit Low

PCM power relay circuit voltage low.

Severity: HighRepair: $30-$500Difficulty: Medium

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Common symptoms of P0686

Common causes of P0686

Repair cost & difficulty

Typical cost to fix P0686: $30-$500 · Difficulty: Medium

Pro tip: Intermittent low voltage to the PCM can cause very confusing symptoms. Check relay contacts and grounds.

Vehicles commonly affected

All makes

Related trouble codes

P0685

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ScanFixAI is a diagnostic aid, not a substitute for professional repair. Cost estimates are typical ranges and vary by vehicle and region.