OBD-II code · Powertrain (generic)
P030B Ignition A Control Signal Circuit Low
Ignition A Control Signal Circuit Low: the signal voltage is below the expected range. This line drives an ignition coil group; a fault causes misfire on those cylinders.
Is it safe to drive with P030B?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyShort to ground
- Less likelyConnector pins corroded - high contact resistance
- Less likelyHarness chafing through insulation
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
- P030EIgnition B Control Signal Circuit Low
- P031BIgnition C Control Signal Circuit Low
- P031EIgnition D Control Signal Circuit Low
- P035BIgnition E Control Signal Circuit Low
- P035EIgnition F Control Signal Circuit Low
- P036BIgnition G Control Signal Circuit Low
- P036EIgnition H Control Signal Circuit Low
- P038BIgnition I Control Signal Circuit Low
- P038EIgnition J Control Signal Circuit Low
- P03FBIgnition K Control Signal Circuit Low
- P03FEIgnition L Control Signal Circuit Low
- P0308Cylinder 8 Misfire Detected
- P0309Cylinder 9 Misfire Detected
- P030CIgnition A Control Signal Circuit High
- P030DIgnition B Control Signal Circuit/Open
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.