P0681 Cylinder 11 Glow Plug Circuit

P0681 indicates a cylinder 11 glow plug circuit problem. The controller detected abnormal continuity, voltage, or current in the cylinder 11 glow plug circuit.

Code details

Generic OBD-II · P0

System: Computer
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not start with module replacement when one cylinder-specific glow plug circuit can be isolated directly.

Symptoms of P0681

Check-engine light, sometimes with several unrelated codes at once.
Warning lights, a no-start, or intermittent electrical faults.
Communication or module-reset problems on a scan tool.

Common causes of P0681

Low battery voltage, poor grounds, corroded connectors, or blown fuses.
Wiring or network (CAN bus) faults between modules.
A module software/programming issue, or rarely a failed controller.

Useful checks before replacing parts

Check cylinder 11 glow plug resistance, module command, voltage drop, current draw, battery condition, and freeze-frame temperature data.
Inspect cylinder 11 wiring, connector corrosion, terminal tension, module output, harness heat exposure, and possible shorts or opens.
Compare cylinder 11 current draw with remaining cylinders to determine whether the fault follows the plug or the control circuit.

Related OBD-II codes

These nearby computer entries can help compare wording and pin down the fault area.