What Does P2329 Mean?
Ignition Coil 'J' Secondary Circuit indicates a fault detected in the high-voltage secondary winding circuit of ignition coil J (cylinder 10). The ECM monitors the ionization current or feedback signal from the secondary circuit and has determined the spark delivery is abnormal, indicating a failed coil, bad plug, or compromised insulation path.
Common Causes
40%
Failed ignition coil J with cracked or open secondary winding
25%
Worn or fouled spark plug on cylinder 10 with excessive electrode gap
20%
Carbon tracking or arc-over in the coil boot or spark plug well
15%
Moisture or oil contamination in the spark plug well
Diagnostic Steps
1
Step 1: Check Mode $06 misfire data to confirm cylinder 10 is actively misfiring and correlates with this secondary circuit code.
2
Step 2: Remove ignition coil J and inspect the coil boot for signs of carbon tracking (black lines), cracks, or burn-through.
3
Step 3: Remove spark plug from cylinder 10 and inspect for worn electrodes, oil fouling, or cracked porcelain. Replace if gap exceeds specification.
4
Step 4: Inspect the spark plug well for oil pooling (indicating a leaking valve cover gasket) or coolant (indicating a head gasket issue).
5
Step 5: Swap ignition coil J with a known-good coil. If the fault moves, replace the coil. If it stays, the plug well or plug is the root cause.
Estimated Repair Cost
$80 - $350
Parts + labor, varies by vehicle and location
Ignition Coil 'J' Secondary Circuit indicates a fault detected in the high-voltage secondary winding circuit of ignition coil J (cylinder 10). The ECM monitors the ionization current or feedback signal from the secondary circuit and has determined the spark delivery is abnormal, indicating a failed ...
The most common cause of P2329 (Ignition Coil "J" Secondary Circuit) is: Failed ignition coil J with cracked or open secondary winding
Typical repair costs for P2329 range from $80 to $350, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Expect misfiring on cylinder 10 with rough idle and reduced power. Continued driving risks catalytic converter damage from unburned fuel passing through.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P2329 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Powertrain
System
Ignition System
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
