Ignition Coil I Primary Control Circuit High
The primary control circuit of ignition coil I reads a voltage above the expected level — typically an open primary circuit or a short to battery voltage on the primary control wire. The ECU sees no normal current flow, coil I does not fire, and the cylinder misfires. Causes: an open or disconnected primary wire, an internal open in the coil, or a faulty ECU driver.
Affected components
- Ignition coil i
- Ignition coil wiring i
- Ignition module
Common causes
- High likelihood: Open circuit in primary winding or harness for coil I
- Low likelihood: Connector pins corroded - high contact resistance
- Low likelihood: Supply wire pinched against B+ source
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.