What does code P1321 mean?

Q: What does code P1321 mean?

Electronic Ignition System Fault Line. P1321 on a GM vehicle indicates that the powertrain control module has detected a fault on the electronic ignition system fault line, which is the communication circuit used to monitor and control the ignition control module or coil driver. The computer is not necessarily reporting a dead ignition component; it is flagging an abnormal voltage or signal condition on that dedicated diagnostic line.

DTC codes / GM codes / P1321

P1321 · GMElectronic Ignition System Fault Line

P1321 on a GM vehicle indicates that the powertrain control module has detected a fault on the electronic ignition system fault line, which is the communication circuit used to monitor and control the ignition control module or coil driver. The computer is not necessarily reporting a dead ignition component; it is flagging an abnormal voltage or signal condition on that dedicated diagnostic line.

SystemPowertrain

Code typeGM specific

SeverityMedium

Fix difficultyIntermediate

AreaIgnition system and misfire

Guidance is general and written for GM vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.