The cylinder 2 glow plug circuit carries high-amp current. The circuit starts at the glow plug relay. It runs through the wiring harness to the cylinder 2 connector. If the wire rubs against the engine block, it will short to ground, setting a code. Corroded terminal pins are also common.
Mechanic Glossary
2 Glow Plug Circuit
The electrical wiring path supplying power from the controller to the cylinder 2 glow plug.
Frequently Asked Questions
A broken wire, a loose harness plug, or corrosion at the glow plug terminal.
Connect a test light to the plug connector. Turn the key on and verify that the light illuminates.
Yes. Glow plug faults are emissions-related, so they will trigger the check engine light.