P0355 on 2003-2012 Honda Accord V6: Ignition Coil 'E' Circuit Causes and Fixes

What's Unique About the 2003-2012 Honda Accord

For the Honda J-series V6 engines used in this Accord, the ignition system is generally robust and known for its longevity. However, like any coil-on-plug system, individual coils can fail with age and heat cycles. The P0355 code is straightforward on this platform and rarely points to complex underlying issues. The key is correctly identifying cylinder #5, which is the middle cylinder on the front bank (closest to the radiator), making it one of the easiest to access and replace. For 8th Gen models (2008-2012) with the J35Z2 engine, it's worth noting that while the Variable Cylinder Management (VCM) system can cause oil fouling on spark plugs for cylinders 1-4, cylinder #5 is not a VCM-affected cylinder, making the diagnosis even more likely to be a simple coil or plug failure.

Generation note: This range covers two Accord generations, both with V6 engines using a coil-on-plug ignition system. The diagnosis and repair are identical, but the ignition coil and spark plug part numbers are different. - 7th Generation (2003-2007): Uses the J30A4/J30A5 3.0L V6. 🎬 Watch: Step-by-step ignition coil replacement for 7th Gen V6 models. - 8th Generation (2008-2012): Uses the J35Z2 (automatic) or J35Z3 (manual) 3.5L V6.

Symptoms You May Notice

• Check Engine Light is on or flashing
• Rough idle or engine shaking
• Engine hesitates or stumbles during acceleration
• Noticeable loss of power, especially under load
• Possible smell of unburned gasoline from the exhaust
• Decreased fuel economy

Most Likely Causes

1. Failed Ignition Coil (Cylinder #5) 🔴 High Probability → Shop Ignition Coil Coils are a common wear item that fail from heat and age. The coil for cylinder #5 is no more prone to failure than others, but it is a frequent cause for this specific code. Heat cycles cause the internal windings to short or break over time.
   How to confirm: Swap the ignition coil from cylinder #5 with the coil from an adjacent cylinder (e.g., cylinder #4 or #6). Clear the codes and drive the car. If the code returns as P0354 or P0356, the coil is faulty.
   Typical fix: Replace the single failed ignition coil. It is not necessary to replace all six unless they are all high-mileage and you prefer to do so for preventative maintenance.
   Est. part cost: $40-$120
2. Worn or Fouled Spark Plug (Cylinder #5) 🟡 Medium Probability → Shop Spark Plug A spark plug with an excessive gap or heavy carbon/oil fouling can strain the ignition coil, causing it to fail or the PCM to detect a circuit fault. Honda V6 engines are known to be sensitive to non-OEM spec (NGK or Denso Iridium) spark plugs, which can cause misfires.
   How to confirm: After confirming the coil is good, remove the spark plug from cylinder #5. Inspect it for wear (worn electrode), damage (cracked porcelain), or fouling (black, oily, or white deposits). Compare it to a plug from a working cylinder.
   Typical fix: Replace the spark plug. It is best practice to replace all six spark plugs at the same time with OEM-spec NGK or Denso plugs to ensure consistent performance.
   Est. part cost: $10-$25 per plug
3. Damaged Wiring or Connector ⚪ Low Probability The plastic connector for the ignition coil can become extremely brittle from engine heat and age, causing the locking tab to snap off during removal. This can lead to a loose connection that vibrates free, causing an intermittent or constant P0355 code. Wires can also be damaged from rubbing or improper handling.
   How to confirm: If a coil swap doesn't move the code, visually inspect the wiring harness and connector for cylinder #5. Wiggle the connector with the engine running to see if it induces a misfire. Check for broken wires, corrosion on the pins, or a broken locking tab.
   Typical fix: Repair the damaged section of wire or replace the connector pigtail. A new pigtail (e.g., Honda P/N 04321-S0K-A00 or aftermarket equivalent) can be spliced in. In a pinch, a zip-tie can temporarily secure a connector with a broken tab. 🎬 Learn how to repair and replace a broken ignition coil connector.
   Est. part cost: $15-$30 for a pigtail

Rare But Worth Checking

• Powertrain Control Module (PCM) Failure: → Shop Engine Control Module (ECM) This is very rare. The internal driver circuit in the PCM that controls the ignition coil can fail. This should only be considered after a new coil, spark plug, and connector/wiring have been confirmed to be good. Diagnosis involves using a multimeter or oscilloscope to check for the trigger signal from the PCM at the coil connector.

Diagnosis Steps

1. Read the trouble codes with an OBD-II scanner to confirm P0355 is present. Note any other codes like P0305.
2. Identify cylinder #5. On the V6 Accord, the cylinders are numbered 1-2-3 on the rear bank (near firewall) and 4-5-6 on the front bank (near radiator), from passenger side to driver side. Cylinder #5 is the middle cylinder on the front bank.
3. Swap the ignition coil from cylinder #5 with the coil from cylinder #4 (to its left) or cylinder #6 (to its right). Mark the coils to keep track of them.
4. Clear the trouble codes using the scanner.
5. Start the engine and let it idle or drive for a few minutes until the Check Engine Light comes back on.
6. Re-scan for codes. If the code is now P0354 or P0356, the ignition coil you moved is faulty and must be replaced.
7. If the code remains P0355, the problem is not the coil. Carefully inspect the wiring connector for cylinder #5. Check for a broken locking tab, corrosion on the pins, or pushed-out terminals.
8. If the wiring appears good, remove and inspect the spark plug in cylinder #5. If it is worn, fouled, or damaged, replace it. It is highly recommended to replace all six plugs as a set with NGK or Denso Iridium plugs.
9. As an advanced step, use a multimeter to check for 12V power and a good ground at the coil connector. Use a noid light or oscilloscope to verify the trigger signal from the PCM.
10. If all the above steps do not resolve the issue, the problem may be a rare failure in the PCM's ignition driver circuit, which requires professional diagnosis or PCM replacement.

Parts You'll Likely Need

• Ignition Coil (7th Gen, 2003-2007) (OEM #30520-RCA-S01) — This is the direct replacement coil for the 3.0L V6 engine and is the most common failure part for a P0355 code.
  Trusted brands: Honda (Genuine), Denso (673-2310), NGK (U5019), Hitachi (IGC0013)
  OEM price range: $80-$120
  Aftermarket price range: $40-$90
• Ignition Coil (8th Gen, 2008-2012) (OEM #30520-R70-A01 (supercedes 30520-R70-S01)) — This is the direct replacement coil for the 3.5L V6 engine and is the most common failure part for a P0355 code.
  Trusted brands: Honda (Genuine), Denso (673-2311), NGK (U5270), Hitachi (IGC0077)
  OEM price range: $85-$125
  Aftermarket price range: $50-$95
• Spark Plug (7th Gen, 2003-2007) (OEM #IZFR6K-11 (NGK) / SKJ20DR-M11 (Denso)) — A worn spark plug can cause this code. It's recommended to replace plugs when replacing a coil. Use of OEM brands is highly recommended on Honda engines.
  Trusted brands: NGK, Denso
  OEM price range: $15-$25
  Aftermarket price range: $10-$20
• Spark Plug (8th Gen, 2008-2012) (OEM #ILZKR7B11 (NGK) / DXE22HR11 (Denso)) — A worn spark plug can cause this code. It's recommended to replace plugs when replacing a coil. Use of OEM brands is highly recommended on Honda engines.
  Trusted brands: NGK, Denso
  OEM price range: $18-$28
  Aftermarket price range: $12-$22
• Ignition Coil Connector Pigtail (OEM #04321-S0K-A00) — Needed if the original connector is broken, corroded, or the wires are damaged. The plastic locking tab is notoriously brittle.
  Trusted brands: Honda (Genuine), Dorman, Carquest (PTA1136)
  OEM price range: $25-$45
  Aftermarket price range: $15-$30

Related Codes That Often Appear With This One

• P0305 — P0305 means 'Cylinder 5 Misfire Detected'. A P0355 fault in the ignition coil circuit will prevent spark, directly causing a misfire in that cylinder.
• P0300 — This code for 'Random/Multiple Cylinder Misfire' can sometimes appear alongside a specific cylinder code if the engine is running very poorly.
• P0304, P0306 — Misfire codes for adjacent cylinders (4 and 6) may appear if the underlying cause is a broader issue like a vacuum leak affecting the front bank, though this is less common for a P0355 primary fault.

Technical Service Bulletins (TSBs) & Recalls

• No specific TSBs were found directly addressing a P0355 fault on the 2003-2012 Honda Accord V6. While Honda has issued TSBs for VCM-related misfires on cylinders 1-4 (e.g., for the Odyssey), these do not apply to cylinder #5. A TSB for Ford trucks (18-2047) describes a similar P0355 issue caused by wiring interference, highlighting that wiring is a plausible, though less common, cause.

Platform-Specific Known Issues

• Brittle Ignition Coil Connectors: → Shop Ignition Coil A very common issue on this platform is the plastic ignition coil connectors becoming brittle from years of heat cycles. The small tab used to release the connector often snaps off when attempting to disconnect it. This can result in a loose connection that causes misfires and sets codes like P0355. If the tab breaks, the connector should be replaced, though a zip-tie can be used as a temporary fix to hold it securely.
• VCM (Variable Cylinder Management) irrelevance for P0355: On the 8th Generation Accord (2008-2012) with the J35Z2 automatic transmission engine, the VCM system deactivates cylinders 1, 2, 3, and 4 under light load to save fuel. This system is known to sometimes cause oil consumption and spark plug fouling on those specific cylinders, leading to misfires. However, cylinder #5 is a non-VCM cylinder. This fact helps reinforce the diagnosis for P0355, as it is not susceptible to VCM-related issues, making a bad coil, plug, or wiring the most probable cause.

Mechanic-Grade Diagnostic Values

• Ignition Coil Connector - Power Pin Voltage — expected: ~12V (Battery Voltage). Failure: 0V indicates a problem with the power supply, likely the #2 (15A) under-dash fuse or the ignition coil relay.
• Ignition Coil Connector - Ground Pin — expected: Good ground continuity to chassis.. Failure: High resistance indicates a break in the ground wire, which runs back to the main engine ground G101.
• Ignition Coil Signal Wire - Continuity to PCM — expected: < 5.0 Ohms. Failure: Higher resistance (or an open circuit) indicates a broken wire between the PCM and the coil connector.

Hidden / Shadow Codes Worth Checking

• Freeze Frame Data: While not a 'shadow code,' the Honda Diagnostic System (HDS) and other advanced scanners can access Freeze Frame data. This is a snapshot of all critical engine sensor values at the exact moment the P0355 code was triggered. This data can reveal conditions (like high engine load or extreme temperature) that may have contributed to the fault, providing clues beyond the code itself. (see via Requires a professional scan tool or the dealer-level Honda HDS software.)

Scan Tool Commands That Help

• Honda HDS (or equivalent professional scanner): Ignition System Test / Coil Activation Test — This is a bidirectional test used when P0355 persists after a coil swap. It allows the technician to command the PCM to fire only the cylinder #5 coil with the engine off. If a spark tester connected to the coil fires, it proves the PCM driver, wiring, and coil are all capable of functioning, pointing to an intermittent issue. If it does not fire, it helps isolate the fault to the PCM driver or wiring, as the coil itself was already tested via swapping.

Wiring & Ground Locations

• G101 — For the 3.0L V6, this main engine and PCM ground is typically located on the engine block or cylinder head, near the intake manifold on the driver's side.. The ignition coils are grounded through the PCM, which relies on G101 for a clean ground reference. A loose or corroded G101 can introduce electrical noise and voltage instability, leading to intermittent misfires, premature coil failure on multiple cylinders, and stubborn circuit codes like P0355.
• Ignition Coil Connector (Cylinder #5) — On top of the valve cover, connected to the middle ignition coil on the front bank of cylinders (closest to the radiator).. This is the direct interface for the component in question. Pin testing is critical. For the 3-pin connector: one pin is 12V+ power (often Black/White), one is ground (Black), and one is the trigger signal from the PCM.
• Under-dash Fuse/Relay Box — Inside the cabin, typically to the left of the steering column.. This box contains the ignition coil relay and fuse #2 (15A), which provides power to all ignition coils. A failure of either component would typically cause a no-spark condition on all cylinders, but intermittent issues could theoretically manifest on one cylinder first.

Real Owner Repair Stories

• Honda Accord Forum user 'KidCubi' (2005 Honda Accord V6 Coupe MT) — Flashing CEL on startup, misfire on a single cylinder (P0305), confirmed P0355.
  ❌ Tried (didn't work) Replacing the failed coil with a new NGK coil (part number 48841) from RockAuto. The replacement coils would fail again on different cylinders (6, 5, then 1) over the course of a year.
  ✅ What actually fixed it The thread concludes with the user and another owner of a 2004 V6 suspecting a bad batch of NGK coils from that specific retailer. The implied fix was to stop using that specific part and likely switch to a different brand like Denso or genuine Honda, or source the NGK part from a different supplier.
• Reddit user on r/MechanicAdvice (2007 Honda Accord V6 Hybrid) — Rough running, CEL for misfires on multiple cylinders including #5. The car was repeatedly 'burning through' new spark plugs and ignition coils every 6-8 weeks.
  ❌ Tried (didn't work) Replacing all coils with a cheap 6-pack from eBay. Replacing a single failed coil. Replacing all spark plugs with new iridium plugs. Having a mechanic replace all coils and plugs with 'OEM certified brands'. The problem continued to return on different cylinders after each fix.
  ✅ What actually fixed it This story is a cautionary tale as the user never posted a final resolution. The pattern of repeated, rolling coil failures strongly suggests an underlying systemic electrical problem (like a faulty alternator creating voltage spikes or a bad engine ground) was destroying the new coils, a problem that is commonly missed when a shop just replaces the currently failed part.

When the Usual Fixes Don't Work

• While a failed ignition coil is the cause of P0355 in over 80% of cases, there are documented instances where even replacing coils with reputable aftermarket brands like NGK did not solve the problem long-term. In these cases, owners experienced repeated failures across different cylinders every few months, suggesting either a widespread quality control issue with a specific batch of aftermarket parts or a deeper, underlying electrical problem (like a faulty alternator or poor engine ground) that was destroying the new coils. This contradicts the idea that a simple one-time coil replacement is always a permanent fix.

OEM Part Supersession History

• 30520-R70-S01 → 30520-R70-A01 — Standard part revision by the manufacturer, likely for improved reliability or a change in supplier.
  Heads up: The parts are interchangeable, with the A01 version being the current replacement for the S01.

Model Year Variations Within This Range

• 2008-2012: The J35Z2 engine in automatic transmission models features Variable Cylinder Management (VCM). This system deactivates the rear bank of cylinders (1, 2, 3) under light load. This is relevant because it means VCM issues (like oil-fouled plugs) are not a cause for faults on cylinder #5, which is on the front bank and is never deactivated.
• 2003-2007 vs 2008-2012: As noted in Pass 2, the ignition coils and spark plugs are different parts between the 7th Gen (3.0L) and 8th Gen (3.5L) engines. Additionally, the specific wire color for the 12V+ supply at the coil connector may vary, with some diagrams showing Black/Yellow and others Black/White.

Diagnostic Flowchart

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: A used part is an excellent choice for the ignition coil connector pigtail. If the original connector's locking tab breaks, sourcing an OEM pigtail from a salvage yard vehicle is often a higher quality and cheaper solution than buying a new aftermarket connector.

Donor-vehicle mileage cap: roughly under 80000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• For a used coil: Ask for the mileage of the donor car; avoid coils from high-mileage engines (>100k miles).
• For a used connector: Inspect the plastic housing for brittleness or cracks. Most importantly, ensure the locking tab is present and flexible. Check that the wire insulation is not frayed or cracked where it enters the connector.

OEM-only on this vehicle (don't cheap out):

• Powertrain Control Module (PCM) - If this rare failure occurs, a new or professionally remanufactured OEM unit is strongly advised to avoid compatibility and software issues.

Aftermarket brands forum-validated for this vehicle:

• Denso
• NGK
• Hitachi

Brands owners have reported issues with on this vehicle:

• Unbranded, low-cost coil sets from online marketplaces (e.g., eBay, Amazon) have a high reported failure rate.
• Caution is advised even with reputable brands from some online retailers, as at least one bad batch of NGK coils was reported by multiple owners for the 2004-2005 models.

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0305 — Cylinder #5 Misfire Detected. This is a direct companion code. The primary circuit fault described by P0355 prevents the spark plug from firing correctly, which the PCM detects as a misfire on the same cylinder.
• P0354 — Ignition Coil 'D' (Cylinder #4) Primary/Secondary Circuit. This code is not a cause, but a diagnostic result. It will appear after swapping a faulty coil from cylinder #5 to cylinder #4, confirming the coil is the problem.
• P0356 — Ignition Coil 'F' (Cylinder #6) Primary/Secondary Circuit. Similar to P0354, this code will appear if a bad coil from cylinder #5 is moved to cylinder #6 during the diagnostic swap test.
• P0351 — Ignition Coil 'A' (Cylinder #1) Primary/Secondary Circuit. This code indicates the same type of fault as P0355, but for cylinder #1. It shares the same common causes: a bad coil, spark plug, or wiring for that specific cylinder.
• P0352 — Ignition Coil 'B' (Cylinder #2) Primary/Secondary Circuit. This code indicates the same type of fault as P0355, but for cylinder #2. It shares the same common causes: a bad coil, spark plug, or wiring for that specific cylinder.
• P0353 — Ignition Coil 'C' (Cylinder #3) Primary/Secondary Circuit. This code indicates the same type of fault as P0355, but for cylinder #3. It shares the same common causes: a bad coil, spark plug, or wiring for that specific cylinder.

Frequently Asked Questions