OBD-II Automotive Error Code P0681: How to Fix It

Q: What does error code P0681 mean?

P0681 indicates a problem with the glow plug control circuit for cylinder 12. It means the powertrain control module (PCM) has detected a malfunction in the electrical circuit that controls the glow plug for that cylinder.

Q: Can I drive with a P0681 code?

You can drive, but you may experience hard starting, especially in cold weather. It's best to fix it promptly to avoid further issues and potential engine damage from incomplete combustion.

Q: How do I test a glow plug?

Use a multimeter set to ohms. Disconnect the glow plug, touch one probe to the glow plug terminal and the other to a good ground. A good glow plug reads 0.5–2 ohms. No continuity means it's bad.

Q: What parts do I need to fix P0681?

You may need a replacement glow plug, possibly a glow plug relay or control module, and dielectric grease or anti-seize compound.

Q: Is P0681 a serious error?

It's moderately serious. While you can still drive, it affects starting and emissions. Ignoring it can lead to more costly repairs if the glow plug seizes or damages the cylinder head.

Abstract

Error code P0681 indicates a fault in the glow plug control circuit for cylinder 12 of your diesel engine. This usually means the glow plug or its circuit is malfunctioning, leading to hard starts in cold weather or a check engine light. This guide will help you diagnose and fix the issue.