Cause
Signal wire shorted to ground
A sensor's output wire touching earth, so the module reads the lowest value the circuit can produce. The reading sits at the extreme rather than merely being wrong, which is the tell — a genuinely failing sensor usually drifts, while a shorted wire pins.
Typically a moderate job.
Codes this can cause (48)
Codes where this is a likely explanation first, rather than merely a possible one.
- P0405 Exhaust Gas Recirculation Sensor A Circuit Low Likely for this code Low
- P0407 Exhaust Gas Recirculation Sensor B Circuit Low Likely for this code Low
- P0427 Catalyst Temperature Sensor Circuit Low Bank 1 Sensor 1 Likely for this code Low
- P0437 Catalyst Temperature Sensor Circuit Low Bank 2 Sensor 1 Likely for this code Low
- P0452 Evaporative Emission System Pressure Sensor/Switch A Circuit Low Likely for this code Low
- P0458 Evaporative Emission System Purge Control Valve A Circuit Low Likely for this code Low
- P0462 Fuel Level Sensor A Circuit Low Input Likely for this code Low
- P0467 Evaporative Emission Purge Flow Sensor Circuit Low Likely for this code Low
- P0472 Exhaust Pressure Sensor A Circuit Low Likely for this code Moderate
- P0477 Exhaust Pressure Control Valve A Low Likely for this code Low
- P0489 Exhaust Gas Recirculation A Control Circuit Low Likely for this code Moderate
- P0498 Evaporative Emission System Vent Valve Control Circuit Low Likely for this code Low
- P0502 Vehicle Speed Sensor A Circuit Low Input Likely for this code Moderate
- P0508 Idle Air Control System Circuit Low Likely for this code Low
- P0516 Battery Temperature Sensor Circuit Low Likely for this code Low
- P0522 Engine Oil Pressure Sensor/Switch A Low Likely for this code High
- P0532 Air Conditioning Refrigerant Pressure Sensor A Circuit Low Likely for this code Low
- P0537 Air Conditioning Evaporator Temperature Sensor Circuit Low Likely for this code Low
- P0541 Intake Air Heater A Circuit Low Likely for this code Low
- P0545 Exhaust Gas Temperature Sensor Circuit Low — Bank 1 Sensor 1 Likely for this code Moderate
- P0548 Exhaust Gas Temperature Sensor Circuit Low — Bank 2 Sensor 1 Likely for this code Moderate
- P0552 Power Steering Pressure Sensor/Switch Circuit Low Likely for this code Low
- P0557 Brake Booster Pressure Sensor Circuit Low Input Likely for this code Moderate
- P0572 Cruise Control Brake Switch A Circuit Low Likely for this code Moderate
- P0576 Cruise Control Input Circuit Low Likely for this code Low
Information, not instruction
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