Ignition Coil B Primary/Secondary Circuit Malfunction
The P0352 code means the vehicle's onboard diagnostic system has detected: Ignition Coil B Primary/Secondary Circuit Malfunction. This is a serious severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- medium
- Estimated cost
- $30-$80 per ignition coil
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Common Symptoms
- Misfire on cylinder(s) served by coil B
- Rough idle
- Check Engine Light on or flashing
- Power loss
Probable Causes (Ranked by Likelihood)
- Failed ignition coil pack or coil-on-plug unit (coil B) Very High
- Open or shorted wiring to coil B High
- Faulty ignition control module Low
Step-by-Step Diagnostic Procedure
-
Swap coil B with a known-good coil from another position. If the misfire follows, replace the coil.
-
Test primary coil resistance: 0.4-2 ohms. Test secondary resistance: 6,000-15,000 ohms.
-
Inspect coil connector for carbon tracking, corrosion, or melted terminals.
-
Verify 12V supply and ground to the coil connector.
Common Fixes by Vehicle
What techs usually find when diagnosing P0352 on specific vehicles — tap your vehicle for the fix and the exact part:
2009-2020 Ford F-150/Explorer 3.5L/5.0L Easy DIY
Ignition coil 2 primary/secondary circuit fault. Swap the coil from cylinder 2 to another cylinder to confirm. If the code follows the coil, replace with Motorcraft DG-549 (EcoBoost) or DG-542 (5.0L). If the code stays on cylinder 2, check the wiring from the PCM to the coil connector. Inspect for chafing where the harness routes along the engine.
Labor: 20-30 min2010-2020 Chevrolet Silverado/GMC Sierra 5.3L Easy DIY
Coil 2 circuit malfunction. Check the connector for corrosion or damage. The 5.3L uses individual coil-on-plug ignition (ACDelco D513A). Measure primary winding resistance (0.4-1.0 ohm). If resistance is out of spec, replace the coil. If the coil is good, check the ECM driver circuit. Swap with a known-good coil from another cylinder to verify.
Labor: 15-20 min2009-2019 Dodge Ram/Chrysler 300 5.7L Hemi Easy DIY
Coil 2 circuit fault on the Hemi. Replace the coil (Mopar 56028394AH) and the spark plug together. Check the coil boot for carbon tracking -- a white powder residue inside the boot indicates arcing. If the code returns, the PCM coil driver may have failed. Also check for a cracked spark plug porcelain that allows voltage to arc to ground.
Labor: 15-20 minFrequently Asked Questions
Which cylinder is coil B?
Coil designations (A, B, C...) correspond to cylinders in firing order sequence, not necessarily the physical cylinder number. On most Ford and GM applications, coil B corresponds to cylinder 2. Consult your service manual.
Sources
This page is built from documented references. Verify against your own service info before repair work.
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