P12A2 on Nissan
Fuel Rail Pressure Sensor Reads Too High (manufacturer-specific)
P12A2 on Nissan vehicles indicates fuel rail pressure sensor reads too high (manufacturer-specific). Au7o has documented this code across 1 Nissan model — most commonly on Pathfinder. P12A2 is a manufacturer-specific powertrain code, common on Volkswagen, Audi, and Porsche, indicating the fuel rail pressure sensor is reporting a pressure the engine control module considers too high or implausible. The ECM monitors rail pressure to precisely control direct fuel injection, and an out-of-range high reading can trigger this code and protective measures. It can be caused by an actual over-pressure condition or by a faulty sensor reporting a false high value, and it may cause misfires, rough running, and reduced power.
Common Causes of P12A2
- •Faulty fuel rail pressure sensor
- •Fuel pressure regulator stuck or malfunctioning
- •High-pressure fuel pump fault
- •Wiring or connector problems at the pressure sensor
- •Clogged fuel filter or restricted return affecting pressure
- •ECM/software calibration issue
- •Faulty ECM
P12A2 on Nissan by Model
Nissan Pathfinder(1 issue)
- Auto Start-Stop System Failure and No-Restart/Stall Events2022-2025
Multiple owners reported the Pathfinder shutting off at a stop with the auto start-stop system and then failing to restart promptly, sometimes displaying warning messages or requiring a manual restart attempt. Nissan issued a safety recall for certain vehicles related to the idle stop/start system because the engine may not restart after an auto stop event, creating a stall condition and increasing crash risk. Complaints often describe the issue occurring at traffic lights or in heavy traffic, with the vehicle briefly immobilized.
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View P12A2 across all makes →Frequently Asked Questions
What does P12A2 mean on Nissan?▼
P12A2 stands for "Fuel Rail Pressure Sensor Reads Too High (manufacturer-specific)." P12A2 is a manufacturer-specific powertrain code, common on Volkswagen, Audi, and Porsche, indicating the fuel rail pressure sensor is reporting a pressure the engine control module considers too high or implausible. The ECM monitors rail pressure to precisely control direct fuel injection, and an out-of-range high reading can trigger this code and protective measures. It can be caused by an actual over-pressure condition or by a faulty sensor reporting a false high value, and it may cause misfires, rough running, and reduced power. On Nissan specifically, this code is documented across 1 model.
What causes P12A2 on Nissan vehicles?▼
Common causes on Nissan: Faulty fuel rail pressure sensor, Fuel pressure regulator stuck or malfunctioning, High-pressure fuel pump fault, Wiring or connector problems at the pressure sensor, Clogged fuel filter or restricted return affecting pressure. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P12A2 on a Nissan?▼
Repair costs vary widely depending on the root cause and specific Nissan model.
Which Nissan models have P12A2 documented?▼
Au7o has documented P12A2 on 1 Nissan model: Pathfinder.