OBD-II code · Powertrain (generic)
P030C Ignition A Control Signal Circuit High
Ignition A Control Signal Circuit High: the signal voltage is above the expected range. This line drives an ignition coil group; a fault causes misfire on those cylinders.
Is it safe to drive with P030C?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyShort to B+
- Less likelyConnector pins corroded - high contact resistance
- Less likelySupply wire pinched against B+ source
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.5–2.5 h
- Emissions test
- Likely to fail
- Parts involved
- Ignition Coil
Related codes
- P030AIgnition A Control Signal Circuit/Open
- P030FIgnition B Control Signal Circuit High
- P031CIgnition C Control Signal Circuit High
- P031FIgnition D Control Signal Circuit High
- P035CIgnition E Control Signal Circuit High
- P035FIgnition F Control Signal Circuit High
- P036CIgnition G Control Signal Circuit High
- P036FIgnition H Control Signal Circuit High
- P038CIgnition I Control Signal Circuit High
- P038FIgnition J Control Signal Circuit High
- P03FCIgnition K Control Signal Circuit High
- P03FFIgnition L Control Signal Circuit High
- P0309Cylinder 9 Misfire Detected
- P030BIgnition A Control Signal Circuit Low
- P030DIgnition B Control Signal Circuit/Open
- P030EIgnition B Control Signal Circuit Low
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.