Faulty alternative fuel tank pressure sensor; Damaged or corroded wiring or connector at the sensor or PCM; Open or short circuit in the sensor signal or reference voltage circuit; Poor ground connection for the sensor or PCM; Failed fuel pressure regulator or mechanical issue causing actual pressure to be out of range; PCM software issue or internal fault (rare)

DTC codes / P01xx · Fuel and air metering / P019E

P019EAlternative Fuel Tank A Pressure Sensor Circuit

Q: What does code P019E mean?

Alternative Fuel Tank A Pressure Sensor Circuit. P019E indicates that the powertrain control module has detected an electrical fault in the circuit for the alternative fuel tank A pressure sensor, which monitors the pressure inside a compressed or liquefied alternative fuel tank. The computer compares the sensor signal voltage against expected values and sets this code when the signal is out of range, intermittent, or absent.

P019E indicates that the powertrain control module has detected an electrical fault in the circuit for the alternative fuel tank A pressure sensor, which monitors the pressure inside a compressed or liquefied alternative fuel tank. The computer compares the sensor signal voltage against expected values and sets this code when the signal is out of range, intermittent, or absent.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering

Symptoms you may notice

Illumination of the malfunction indicator lamp, often with no other noticeable symptoms
Rough running or hesitation if the vehicle switches to gasoline operation due to the fault
Reduced power or a fail-safe mode that limits engine speed
Incorrect or erratic fuel gauge readings for the alternative fuel tank
Difficulty refueling or a refueling system that stops prematurely
A message on the driver information center indicating an alternative fuel system fault

Common causes, most likely first

Faulty alternative fuel tank pressure sensor
Damaged or corroded wiring or connector at the sensor or PCM
Open or short circuit in the sensor signal or reference voltage circuit
Poor ground connection for the sensor or PCM
Failed fuel pressure regulator or mechanical issue causing actual pressure to be out of range
PCM software issue or internal fault (rare)

How to diagnose and fix it

Connect a scan tool and record freeze-frame data and any related codes to understand the conditions when the fault set
Visually inspect the sensor, its connector, and the wiring harness for damage, corrosion, or loose pins
Measure reference voltage (usually 5V) and ground at the sensor connector with the key on, engine off
Check the sensor signal voltage with a multimeter or oscilloscope while monitoring live data to see if it tracks pressure changes
Perform a voltage drop test on the ground and power circuits to rule out resistance issues
If the sensor signal is erratic or out of range, replace the sensor and clear codes to verify the repair
If wiring is faulty, repair or replace the affected section of the harness and recheck

Don't overlook the pressure sensor connector

A common oversight is assuming the sensor itself has failed when the real problem is a corroded connector pin or chafed wire that only acts up under vibration or temperature changes.
The code can set due to a mechanical pressure issue, such as a failing regulator or a tank that is over-pressurized, so always verify actual pressure with a gauge before condemning the sensor.
On some vehicles, a weak battery or charging system can cause erratic sensor readings that mimic a circuit fault, so check system voltage first.
After replacing the sensor, some systems require a relearn or calibration procedure with a scan tool to avoid a repeat code.
This code is specific to alternative fuel systems and will not set on vehicles that do not have a separate alternative fuel tank pressure sensor circuit.

Can I keep driving with P019E?

You can usually continue driving if the vehicle runs normally, but avoid aggressive acceleration or heavy loads until the fault is repaired. If the vehicle enters a reduced-power mode or you smell fuel, stop driving and have it towed to a repair shop.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.