What P1400 means
This is a diagnostic trouble code (DTC) reported by your vehicle's onboard OBD-II system when a specific fault is detected in the powertrain.
Common causes (general)
Before spending money on parts, verify the code with a scan tool and read freeze frame data. Freeze frame captures every sensor value at the moment the code set — this is often enough to figure out the root cause without further testing.
Manufacturer-specific descriptions
Different manufacturers use this code for slightly different failure modes. Here's what your specific make means by P1400:
| BMW | Heated Catalyst Battery Voltage or Current too Low During Heating (Bank 1); Heated Catalyst Battery Voltage or Current too Low during Heating (Bank 1) |
| CHRYSLER | Manifold Differential Pressure Sensor Circuit Malfunction; Exhaust Gas Recirculation Valve Position Control; Differential Pressure Feedback Electronic Sensor Circuit Low Voltage |
| FORD | Differential Pressure Feedback Electronic Sensor Circuit Low Voltage |
| GM | Exhaust gas recirculation (EGR) valve actuator - circuit malfunction |
| JAGUAR | Exhaust Gas Recirculation Valve Postion Control |
| LEXUS | Sub-TP Sensor Malfunction |
| LINCOLN | Differential Pressure Feedback Electronic Sensor Circuit Low Voltage |
| MAZDA | DPFE Sensor Circuit Low Input |
| MERCURY | Differential Pressure Feedback Electronic Sensor Circuit Low Voltage |
| MITSUBISHI | DPFE Circuit Low Input; Manifold differential pressure sensor fault; MDP sensor |
| NISSAN | DPFE Circuit Low Input; EGRC Solenoid/V |
| OTHER | DPFE Circuit Low Input |
| SUBARU | Fuel Tank Pressure Control Solenoid Low Input |
| TOYOTA | Sub-Throttle Position Sensor |
| VOLKSWAGEN | EGR Valve Circuit Electrical Malfunction |
Read this code on your own car
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