What it means
The 5 V reference G voltage is above the expected level. Typical causes are a short to battery or an internal regulator failure.
At a glance
- Usually lights the check-engine light
How it works
The engine control module regulates a 5 V supply on reference circuit G for connected sensors. P262E sets when the monitored G voltage rises above its expected range, which can result from a wire touching battery voltage or a fault in the reference regulator.
Common causes
Most likely first.
- Reference wire shorted to a B+ supply
- Internal 5 V regulator failed
- Connector pins corroded - high contact resistance
Symptoms
- Check-engine light
- Rough running, reduced power, or stalling
- Other sensor-related warning lights may appear
How to diagnose it
- Record freeze-frame data and check for other sensor or reference-voltage codes that could identify affected circuits.
- Inspect circuit G wiring and connectors for damage, corrosion, moisture, or contact with a battery-positive wire.
- Use the wiring diagram to identify sensors on reference G, then disconnect them one at a time while monitoring the rail voltage.
- If disconnecting a sensor changes the voltage, inspect that sensor and its connector for damage or a short to a higher-voltage supply.
- If the voltage remains high with the sensors disconnected, check the G wire for a short to battery voltage and test the module output against the manufacturer's specification.
Common fixes
- Clean and secure corroded connector pins or repair water-damaged connectors.
- Repair a reference wire that is shorted to battery voltage.
- Replace a sensor or connector that is feeding excess voltage into circuit G.
- Repair the module's reference regulator only after confirming the wiring and connected sensors are sound.
Can I keep driving?
Drive only if the engine runs predictably; a high reference voltage can affect several sensors and cause rough running, reduced power, or stalling. Avoid heavy loads and stop if the vehicle becomes difficult to control or repeatedly stalls.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.