Fuel level sensor 'B' signal wire shorted to battery voltage or a 5-volt reference; Open internal resistance element inside the fuel level sensor 'B' sending unit; Corroded, bent, or pushed-back pins at the sensor connector or PCM connector; Damaged wire harness between the sensor and the PCM, often from chafing or rodent damage; Failed fuel level sensor 'B' float or arm mechanism stuck in the full position; PCM internal fault on the fuel level input circuit, though this is rare

DTC codes / P20xx · Fuel and air metering and auxiliary emission controls / P2068

P2068Fuel Level Sensor 'B' Circuit High

Q: What does code P2068 mean?

Fuel Level Sensor 'B' Circuit High. P2068 indicates that the powertrain control module detected an abnormally high voltage on the fuel level sensor 'B' circuit, which typically means the signal wire is shorted to power or the sensor's internal resistance has gone open. The computer expects a voltage within a calibrated range that corresponds to a valid fuel level, and a reading above that range sets this code.

P2068 indicates that the powertrain control module detected an abnormally high voltage on the fuel level sensor 'B' circuit, which typically means the signal wire is shorted to power or the sensor's internal resistance has gone open. The computer expects a voltage within a calibrated range that corresponds to a valid fuel level, and a reading above that range sets this code.

SystemPowertrain

Code typeGeneric (all makes)

SeverityLow

Fix difficultyIntermediate

AreaFuel and air metering and auxiliary emission controls

Symptoms you may notice

Fuel gauge reads completely full or pegged past full at all times
Fuel gauge fluctuates erratically or drops to empty intermittently
Often no symptoms besides the warning light, especially if the vehicle uses a secondary sensor for gauge display
Incorrect distance-to-empty or fuel range calculation on the driver information display
A fuel level-related message or reduced power mode on some vehicles with dual tanks

Common causes, most likely first

Fuel level sensor 'B' signal wire shorted to battery voltage or a 5-volt reference
Open internal resistance element inside the fuel level sensor 'B' sending unit
Corroded, bent, or pushed-back pins at the sensor connector or PCM connector
Damaged wire harness between the sensor and the PCM, often from chafing or rodent damage
Failed fuel level sensor 'B' float or arm mechanism stuck in the full position
PCM internal fault on the fuel level input circuit, though this is rare

How to diagnose and fix it

Connect a scan tool and read live fuel level sensor 'B' voltage to confirm the high reading matches the code
Visually inspect the sensor connector and harness for corrosion, chafing, or loose pins, and repair as needed
Disconnect the sensor and measure reference voltage and ground at the connector to verify the circuit is not shorted to power
Check resistance across the sensor terminals through its full sweep and compare to the manufacturer's specification
Perform a voltage drop test on the signal wire from sensor to PCM to rule out an open or high-resistance circuit
Replace the fuel level sensor 'B' sending unit if resistance is out of specification or the float is stuck
Clear the code and verify the fuel gauge reads correctly through a full-to-empty sweep before returning the vehicle

What a pegged fuel gauge really tells you

A sensor circuit that reads high voltage almost always means an open circuit or a short to power, not a failed gauge cluster, so diagnose the wiring before condemning the instrument panel.
Many vehicles use two fuel level sensors for a saddle-style tank, and sensor 'B' may only be active above or below a certain fuel level, so the fault can hide when the tank is full or empty.
After replacing a fuel level sensor, some vehicles require a fuel gauge calibration or a relearn procedure with a scan tool, and skipping it can leave the gauge inaccurate or the code returning.
Rodent damage to the fuel tank pressure and level sensor harness is a common cause that technicians miss when they focus only on the sensor itself.
A shorted fuel level sensor 'B' circuit can sometimes affect other sensors sharing the same 5-volt reference, so check for multiple codes before assuming a single sensor failure.

Can I keep driving with P2068?

The vehicle remains safe to drive because this fault only affects fuel level reporting, but you should refuel based on mileage rather than the gauge until it is repaired. Avoid relying on the distance-to-empty display, as it may be inaccurate and could leave you stranded.

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.