The ignition coil is considered a major component of your vehicle engine. It helps to ensure the efficient working of the engine. The P0352 code indicates an issue with the ignition coil.
The ignition coil of your vehicle takes voltage from the battery, converts it into high voltage, and transfers it to the spark plug. The powertrain control module (PCM) constantly monitors the performance of the ignition coils. As the ignition coil primary/secondary circuit goes bad, your PCM triggers the P0352 code. This article mainly explains the P0352 code causes, symptoms, and how to fix it.
P0352 Code Definition
P0352 code stands for “Ignition Coil “B” Primary/Secondary Circuit Malfunction.”
What Does Code P0352 Mean?
The P0352 code indicates that your powertrain control module (PCM) detects an issue with the ignition coil “B” (cylinder #2) or its circuit.
The ignition coil is basically a transformer that takes low-voltage current from the vehicle battery and converts it into high voltage according to the spark plug requirements. The spark plug uses this high-voltage current to generate a spark which is used to ignite the fuel-air mixture and make the combustion process successful.
A coil pack generally produces a voltage between 70,000 and 100,000 Volts.
The coil pack is also called an ignition coil. The main function of the coil pack is to convert standard battery voltage to higher voltages required to ignite the fuel-air mixture.
It is a naturally high-voltage generator consisting of two coils:
- Primary coil
- Secondary coil
A large primary coil gets the initial battery voltage and transmits it to a small secondary coil.
The secondary coil is installed in the primary coil, which creates a magnetic field by rotating rapidly inside the primary coil. This helps generate the high voltage and current required to ignite the fuel during the combustion process.
The DTC P0352 is logged when there is a problem with the coil number 2 driver circuit. According to the car model, the PCM may also turn off the fuel injectors for each cylinder.
Causes of P0352 Code
The P0352 code is triggered due to one or more of the following causes:
- Bad ignition coil on cylinder #2
- Bad spark plug
- Corroded or damaged wires of the second cylinder coil pack
- A faulty coil driver circuit
- An issue with the ignition system
- Damaged wiring harness between the PCM and coil pack
- Vacuum leaks
- Blocked throttle body because of carbon accumulation
- Electrical issues within the ignition coil circuit, such as a bad camshaft position sensor, crankshaft position sensor, or other issues
- Blockage of air passages in the throttle body
- Faulty PCM/ECM
Symptoms of P0352 Code
A vehicle with the P0352 code produces one or more of the following symptoms:
- Check engine light illumination
- Poor fuel economy
- Engine misfires
- Hard to start the vehicle
- Rough or abnormal vibrations while driving
- Poor engine performance
- Rough idle
Read More: P0351 Code Symptoms and Causes
How to diagnose the P0352 Code?
To diagnose the P0352 code, follow the following steps:
- Firstly, you need to ensure the presence of the P0352 code by using an OBD2 scan tool.
- Use the freeze frame data to check what’s going on. Continue the troubleshooting based on the other trouble codes stored in the PCM memory.
- After inspection and major repairs, clear the codes.
- Make a test drive. If the P0352 code returns, then move for further inspection.
- Perform a resistance test on the suspected coil pack
- Inspect the physical situation of the spark plug electrodes
- Measure the voltage present at the coil pack
- Check the wiring connecting to the coil pack for damage and corrosion
- Inspect the ignition coil connectors and PCM connectors.
- Perform an inspection of the second cylinder coil pack circuit for a proper ground supply
- Properly inspect the intake manifold for a vacuum leak
- Inspect the second cylinder spark plug.
- Check the primary ignition coil. If it is damaged, replace it.
- Check the Hertz signal sent from PCM to a coil pack by using a multimeter to measure. This step helps to confirm whether your PCM is working perfectly or not.
Common P0352 Code Diagnostic Mistakes
- Not measuring the hertz signal that the PCM should send to the coil pack
- Replacing the parts without testing
- Not inspecting the wiring and connections before replacing the spark plug or coil packs
- Replacing the unnecessary parts
- Clearing the PCM memory without first confirming the problem
- Not clearing the PCM codes after fixing the code.
What repairs can fix the P0352 Code?
One or more of the following repairs can fix the P0352 code:
- Fixing or replacing the damaged coil pack wires
- Replacing the bad spark plug located at cylinder number 2
- Replacing or cleaning the throttle body
- Fixing the vacuum leaks
- Replacing the coil pack for cylinder number 2
- Replacing the powertrain control module (PCM) if needed
P0352 Code Repair Cost
After diagnosing, the P0352 code may need one or more of the following repairs to fix the original problem:
| Parts | Cost |
| Ignition coil replacement | $160 to $220 |
| Vacuum leak repair | $70 to $380 |
| Spark Plug replacement | $60 to $260 |
| PCM replacement | $240 to $3,000 |
How serious is the P0352 code?
The P0352 code is a serious error code. It makes the vehicle difficult to drive. Driving with a misfiring engine has a negative effect on your engine. Because if one of your engine cylinders is stalled, the other cylinders will have to work harder to keep the car running. This puts extra pressure on other cylinders and can cause components such as the crankshaft, piston, spark plug, piston rings, and other coil packs to wear out faster.
Therefore, you should address this code as soon as possible because if you do not fix it on time, it may damage your catalytic converter.
FAQ Section
How do I fix the P0352 code?
You need one or more of the below-given repairs to fix the P0352 code:
- Fixing or replacing the damaged coil pack wires
- Replacing the bad spark plugs
- Replacing or clearing the throttle body
- Fixing the vacuum leak
- Replacing the coil pack for cylinder number 2
- Repairing or replacing the damaged connectors
- Replacing the PCM if needed
Where is the ignition coil B secondary circuit?
The location of ignition coil “B” varies according to the vehicle model but generally indicates the ignition coil on cylinder number 2. In the case of the latest vehicle models, the secondary circuit of the ignition coil typically contains a spark plug and a secondary winding in the coil-on-plug ignition coil.
Can I just replace one ignition coil?
Yes, you can replace one coil at a time or all coils simultaneously. However, we recommend replacing all spark plugs with coils to avoid having to remove the coil twice.
What are the causes of a bad Ignition Coil?
- Wear and tear of the ignition coil
- Bad spark plug
- Bad fuel injector
- Faulty vehicle battery
- Excessive spark plug gap
- Engine overheating
- Connecting the Wrong Ignition Cable