Ignition Coil D Primary Control Circuit Low
The P2306 code means the vehicle's onboard diagnostic system has detected: Ignition Coil D Primary Control Circuit Low. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- moderate
- Estimated cost
- $50 - $300 (parts and labor)
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Common Symptoms
- Misfire on cylinder 4
- Check Engine Light flashing or on
- Vibration felt through steering wheel at idle
- Reduced engine performance
- Exhaust has rough or uneven sound
Probable Causes (Ranked by Likelihood)
- Failed ignition coil D Very High
- Damaged wiring to coil D High
- Corroded connector at coil D Moderate
- Fouled or cracked spark plug on cylinder 4 Moderate
Step-by-Step Diagnostic Procedure
-
Swap coil D with another cylinder coil to verify
-
Inspect spark plug on cylinder 4 for damage or fouling
-
Check coil D connector and wiring for damage
-
Measure coil D primary resistance
-
Check for oil contamination in the spark plug well
Frequently Asked Questions
Can I drive with code P2306?
Short distances only. Address the misfire quickly to prevent catalytic converter damage.
What causes P2306?
Almost always a failed ignition coil on cylinder 4. Replace the spark plug at the same time for the best outcome.
Is P2306 expensive to fix?
Typically $50 to $300. One of the more affordable engine repairs, especially for four-cylinder engines where coil access is easy.
Sources
This page is built from documented references. Verify against your own service info before repair work.
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