P0352
Ignition Coil B Circuit Malfunction
The engine computer detected a problem with the ignition coil circuit for coil B. This can cause misfires, rough running, poor fuel economy, and hard starting.
- SEV
- 4/5
- DRIVE
- CAUTION
- DIY
- $20–$120
- SHOP
- $120–$450
Quick answer
AI-CITATION READYWhat it means
Can you drive with it?
Most common causes
- Failed ignition coil B
- Damaged wiring or loose connector at coil B
- Corroded, bent, or pushed-out terminal in the coil connector
Typical repair cost
DIY usually runs $20–$120. Typical shop repair lands around $120–$450, depending on the root cause.
01 / Definition
P0352 means the powertrain control module detected an electrical fault in the ignition coil B primary or secondary circuit. This can be caused by a failed coil, wiring problem, connector issue, or a driver fault inside the engine control system. The code is often set when the PCM sees an open circuit, short circuit, or abnormal coil control signal.
02 / Drive status
With caution. You may be able to drive short distances, but the engine can run rough and may lose power. Continued driving can damage the catalytic converter and worsen the misfire.
03 / Symptoms
- Check engine light
- Rough idle
- Engine misfire
- Loss of power
- Poor fuel economy
- Hard starting
- Stalling
- Engine hesitation or surging
04 / Causes
| 1 | Failed ignition coil B | high |
|---|---|---|
| 2 | Damaged wiring or loose connector at coil B | high |
| 3 | Corroded, bent, or pushed-out terminal in the coil connector | medium |
| 4 | Faulty spark plug causing high coil load or misfire | medium |
| 5 | PCM driver circuit problem | low |
| 6 | Blown fuse, relay issue, or power supply problem to the ignition coils | low |
05 / Diagnostic sequence
- 01Confirm the code and check for related misfire codes such as P0300 or P0302/P0304 depending on the engine.
- 02Inspect ignition coil B, its connector, and the wiring harness for damage, oil intrusion, corrosion, or looseness.
- 03Check for battery voltage and good ground or control signal at the coil connector using a test light or multimeter.
- 04Swap coil B with another cylinder coil if the vehicle design allows, then see whether the fault follows the coil.
- 05Inspect the spark plug on that cylinder for wear, fouling, cracking, or improper gap.
- 06Use a scan tool or oscilloscope to verify the PCM is commanding the coil correctly.
- 07If wiring and the coil are good, test the circuit back to the PCM for continuity, shorts, and resistance.
- 08Only after all external checks pass, consider PCM driver diagnosis.
06 / Repairs
| 1 | Repair loose, damaged, or corroded wiring and connector terminals at ignition coil B | $20–$150 |
|---|---|---|
| 2 | Replace ignition coil B if it fails testing or the code follows the coil | $40–$180 |
| 3 | Replace worn or damaged spark plug on the affected cylinder | $10–$60 |
| 4 | Repair power, ground, fuse, or relay issues in the ignition coil supply circuit | $15–$120 |
| 5 | Repair PCM circuit faults or replace/program the PCM if all other components test good | $300–$1,200 |
07 / Related codes
08 / FAQ
What does ignition coil B mean?
It usually refers to one specific ignition coil identified by the engine manufacturer. The exact cylinder depends on the vehicle's coil numbering system.
Can a bad spark plug cause P0352?
Yes. A worn or damaged spark plug can overload the coil or contribute to misfire, which may help trigger this code.
Will replacing the coil fix P0352?
Sometimes, but not always. Wiring, connector problems, and PCM driver faults can also cause the code.
Is P0352 the same as a misfire code?
No. P0352 is an ignition coil circuit fault code, but it can cause a misfire and often appears with misfire codes.
09 / Source and method
- DATA BASIS
- OBD-II REFERENCE + OBD2.HELP
- METHOD
- STATIC VALIDATION
- SAFETY
- INFORMATIONAL
This page combines OBD-II diagnostic reference data with OBD2.help generated diagnostic guidance for code meaning, likely causes, and repair direction.
Publishing uses deterministic schema and build validation, plus manual spot checks on representative pages before release.
Safety-critical diagnosis and repairs should be confirmed with a qualified mechanic, especially when the vehicle is misfiring, overheating, or losing power.