A short to ground on the sensor power supply circuit C, such as a chafed wire touching metal; A faulty sensor internally shorted on that reference circuit, pulling the voltage down; Corroded or loose connector terminals at the PCM or at any sensor sharing circuit C; Water intrusion into a connector or splice pack causing a partial short; A damaged PCM driver for the sensor reference voltage, though this is less common; Aftermarket accessories improperly tapped into the reference circuit

DTC codes / P06xx · Computer and output circuits / P06E7

P06E7Sensor Power Supply C Circuit Low

Q: What does code P06E7 mean?

Sensor Power Supply C Circuit Low. P06E7 indicates that the powertrain control module (PCM) has detected a low-voltage condition on the sensor power supply circuit labeled 'C'. This circuit typically provides a regulated 5-volt reference to multiple sensors, and a low reading means the PCM sees the supply voltage below its expected threshold, which can disable or skew sensor readings.

P06E7 indicates that the powertrain control module (PCM) has detected a low-voltage condition on the sensor power supply circuit labeled 'C'. This circuit typically provides a regulated 5-volt reference to multiple sensors, and a low reading means the PCM sees the supply voltage below its expected threshold, which can disable or skew sensor readings.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaComputer and output circuits

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms
Multiple sensor-related trouble codes stored alongside P06E7
Rough running or poor fuel economy if the affected sensors include those for air or fuel metering
Intermittent stalling or hesitation if the low supply affects critical engine sensors
Transmission shift quality issues if the circuit powers a transmission sensor
Reduced engine power or limp mode in some vehicles when the fault is severe

Common causes, most likely first

A short to ground on the sensor power supply circuit C, such as a chafed wire touching metal
A faulty sensor internally shorted on that reference circuit, pulling the voltage down
Corroded or loose connector terminals at the PCM or at any sensor sharing circuit C
Water intrusion into a connector or splice pack causing a partial short
A damaged PCM driver for the sensor reference voltage, though this is less common
Aftermarket accessories improperly tapped into the reference circuit

How to diagnose and fix it

Use a scan tool to record all stored codes and freeze-frame data, then clear codes and verify whether P06E7 returns immediately
Obtain the wiring diagram for the specific vehicle and identify every sensor and splice on the sensor power supply circuit C
Disconnect each sensor on circuit C one at a time and observe whether the reference voltage returns to normal, isolating the faulty component
Perform a voltage drop test on the circuit while loaded with a known-good sensor or a test light to check for excessive resistance
Inspect connectors and harness routing for corrosion, chafing, or water intrusion, repairing terminals or replacing damaged wire sections as needed
If the circuit and all sensors test good, check the PCM reference voltage output directly at the connector; replace the PCM only if it fails the output test
After repair, clear codes and complete a drive cycle to confirm the code does not reset and all sensor readings are within specification

What a low reference voltage really means

A single shorted sensor on a shared 5-volt reference circuit can pull down the voltage for every other sensor on that circuit, so the code may point to circuit C while the actual fault is in a sensor you would not expect.
Technicians often replace the PCM prematurely when the real problem is a chafed harness behind the engine or near a sharp bracket, so always inspect wiring before condemning the module.
P06E7 can be set by a completely different sensor than the one you are diagnosing, because circuit C may feed sensors for power steering, air conditioning, or other systems not directly related to engine performance.
Intermittent low voltage on a reference circuit often leaves no freeze-frame data, so a wiggle test of the harness while monitoring live sensor voltages is more reliable than static checks.
Some vehicles use a dedicated power supply circuit for each sensor group, and a low voltage on circuit C may be caused by a failing voltage regulator inside a sensor that only acts up when hot.

Can I keep driving with P06E7?

You can usually drive the vehicle to a repair shop if the engine runs normally and the check engine light is steady, but avoid heavy acceleration or long trips because the fault can worsen and cause stalling or limp mode. If the engine runs rough, stalls, or the light flashes, stop driving and have the vehicle towed.

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.