P0352 on 2008-2013 Toyota Highlander 3.5L V6: Ignition Coil 'B' Causes and Fixes

What's Unique About the 2008-2013 Toyota Highlander

The 2GR-FE engine, used across many Toyota and Lexus models from this era, is known for this specific type of ignition coil failure. The issue is common enough that Toyota released an updated ignition coil (part number 90919-A2004, which supersedes earlier versions like 90919-02251) to improve reliability. Unlike a generic misfire code (like P0302), the P0352 code is very specific to the coil's electrical circuit, making diagnosis more direct. Often, the check engine light will appear before any significant drivability issues like rough idling are felt, though a single 'hiccup' may be felt at the moment the fault is registered.

Symptoms You May Notice

• Check Engine Light is on
• Flashing Check Engine Light during acceleration
• Slight engine hesitation or stumble, especially under load
• Rough idle (though sometimes symptoms are not noticeable at first)
• VSC and/or TRAC lights may also illuminate, which is a common Toyota response to any engine fault code
• A single, momentary engine shudder or 'miss' as the code is triggered, then seemingly normal operation

Most Likely Causes

1. Failed Ignition Coil (Cylinder #2) 🔴 High Probability → Shop Ignition Coil Early versions of the ignition coils for the 2GR-FE engine were known to fail. Toyota later issued a revised part (90919-A2004 and subsequent revisions) to address the problem.
   How to confirm: Swap the ignition coil from cylinder #2 with the coil from cylinder #4 (the middle cylinder on the same front bank). Clear the codes. If the code changes to P0354 (for cylinder #4), the coil is bad. Cylinder #2 is on the front bank (near the radiator), on the passenger side.
   Typical fix: Replace the faulty ignition coil. It is recommended to replace the corresponding spark plug at the same time if it is near its service interval or shows signs of wear.
   Est. part cost: $40-$100
2. Damaged Wiring or Connector ⚪ Low Probability The plastic connectors and wiring insulation can become brittle over time due to engine heat cycles, but this is less common than outright coil failure.
   How to confirm: If the code P0352 returns after swapping coils, visually inspect the wiring harness and connector for cylinder #2's coil. Check for brittle or cracked plastic on the connector, corrosion on the pins, or broken/chafed wires. Wiggle the connector with the engine running to see if it induces a misfire.
   Typical fix: Repair the damaged section of the wiring harness or replace the connector pigtail.
   Est. part cost: $10-$30

Rare But Worth Checking

• Faulty Engine Control Module (ECM): → Shop Engine Control Module (ECM) This is extremely rare. The ECM should only be considered a possibility after all other causes (coil, spark plug, wiring) have been definitively ruled out.

Diagnosis Steps

1. Read the trouble codes with an OBD-II scanner to confirm P0352 is present.
2. Identify cylinder #2. On the transverse 2GR-FE, the bank near the radiator is Bank 2, containing cylinders 2, 4, and 6, from the passenger side (timing cover side) to the driver side. Cylinder #2 is the first one on the front bank, passenger side.
3. Swap the ignition coil from cylinder #2 with the coil from cylinder #4 (the middle coil on the front bank). This is an easy and definitive test that requires only a 10mm socket. While the connector is off, inspect it for cracks or corrosion.
4. Clear the trouble codes using the scanner.
5. Start the engine and let it run for a minute, then take a short drive. The check engine light will likely return quickly.
6. Re-scan for codes. If code P0354 appears, the ignition coil you moved is faulty and must be replaced.
7. If code P0352 returns, the problem is not the coil. Proceed to inspect the wiring harness and connector for cylinder #2 for any signs of damage, corrosion, or loose pins.
8. If the wiring appears perfect, the next step would be to check the spark plug, although it's a less likely cause for this specific code. An extremely rare cause could be a fault in the ECM's ignition driver circuit.

Parts You'll Likely Need

• Ignition Coil (OEM #90919-A2004) — This is the most common failure point for code P0352 on this engine. The part number listed is a revised version from Toyota, designed for better durability. It supersedes older numbers like 90919-02251 and has itself been superseded by 90919-A2013, which are all interchangeable.
  Trusted brands: Denso (OEM), NGK, Bosch, Hitachi
  OEM price range: $90-$120
  Aftermarket price range: $40-$70

Related Codes That Often Appear With This One

• P0302 — If the coil fails completely, it will cause a misfire in cylinder #2, logging a P0302 'Cylinder 2 Misfire Detected' code alongside the P0352 circuit code.
• P0300 — In some cases, a fault in one coil circuit can cause the ECM to log a 'Random/Multiple Cylinder Misfire' code as a pending fault before isolating it to the specific cylinder.

Platform-Specific Known Issues

• The 2GR-FE engine had a known issue with premature ignition coil failures in its early years, prompting Toyota to release an updated part (90919-A2004).
• Cylinder #2 is located on the front bank (Bank 2), which is easily accessible without removing the intake manifold, making this a simple repair compared to coils on the rear bank (Bank 1).
🎬 See this step-by-step walkthrough for replacing Highlander coils and plugs.

Mechanic-Grade Diagnostic Values

• Ignition Coil Primary Resistance — expected: 0.5 Ω ± 0.1 Ω. Failure: A reading outside this range, especially an open circuit (infinite resistance), indicates a faulty coil.
• Ignition Coil Secondary Resistance — expected: ~12 kΩ. Failure: A significantly different reading suggests an internal failure of the coil's secondary winding.
• IGT (Ignition Trigger) Signal at ECM — expected: Pulsing square wave, approximately 0V to 5V, when engine is cranking or running.. Failure: No waveform or a flat line indicates a problem with the ECM or the wiring between the ECM and the coil.
• IGF (Ignition Confirmation) Signal at ECM — expected: Pulsing square wave, similar to IGT but may have a slightly different duty cycle, confirming the coil has fired.. Failure: No waveform when the IGT signal is present confirms a fault in the coil's internal igniter or the IGF circuit wiring. This is the direct trigger for code P0352.
🎬 Watch: A mechanic's guide to fixing P035x circuit codes.
• Ignition Coil Power Supply Voltage — expected: Battery voltage (approx. 12V) at Pin 1 (+B) of the coil connector with ignition ON.. Failure: Voltage below 9V or no voltage indicates a problem with the power supply from the IG2 relay or a wiring fault.

Scan Tool Commands That Help

• Toyota Techstream: Active Test: 'Control the Injection Volume' — While not a direct coil test, a technician can use this to disable fuel to individual cylinders one by one. If disabling fuel to cylinder #2 causes no change in engine idle, it confirms that cylinder was not contributing, strongly pointing to an ignition issue (the likely P0352 cause) or a compression problem.
🎬 Watch: How to troubleshoot and fix ignition coil circuit problems.

Wiring & Ground Locations

• Ignition Coil #2 Connector — On the front cylinder bank (Bank 2), passenger side. It is a 4-pin connector.. This is the primary connection point for testing. The pins are: Pin 1 (+B, Power), Pin 2 (IGT, Trigger from ECM), Pin 3 (IGF, Confirmation to ECM), Pin 4 (GND, Ground).
• Ground Point EB — On the right front fender apron, near the main engine room relay block.. This is a major ground point for the engine wiring harness. While the coil grounds directly through the harness to the ECM ground circuit, a poor main engine ground at this location can cause a variety of unpredictable electrical issues, including ignition problems.
• ECM (Engine Control Module) — Behind the right side of the dashboard / glove box area.. This is the source of the IGT signal and the destination for the IGF signal. Advanced diagnosis requires testing for signals at the ECM connectors if a wiring fault is suspected between the ECM and the coil.

Real Owner Repair Stories

• YouTube video 'P0352 Code FIX & EXPLINATION' (Lexus/Toyota V6 (similar to 2GR-FE)) — P0352 code stored.
  ✅ What actually fixed it The video demonstrates the standard, and most often successful, diagnostic procedure: swapping the ignition coil from the faulting cylinder (#2) to another cylinder (#4). If the code follows the coil (changing to P0354), the coil is confirmed bad and is replaced.

OEM Part Supersession History

• 90919-02251 → 90919-A2002, then 90919-A2004, then 90919-A2007, and finally 90919-A2013 — Revisions to improve durability and address premature failure rates common in early 2GR-FE engines.
  Heads up: All listed part numbers are interchangeable. When replacing, it is best to use the latest available revision (e.g., 90919-A2013 or a reputable aftermarket equivalent).

Model Year Variations Within This Range

• 2011-2013: The Highlander received a mid-cycle refresh for the 2011 model year, which included a revised front fascia, new headlights, and updated interior tech packages. However, the core 3.5L 2GR-FE engine and its ignition system remained unchanged, so the diagnosis and repair for code P0352 are identical for the entire 2008-2013 range.

Diagnostic Flowchart

Other Known Issues on This Vehicle

Issues unrelated to this code that are worth knowing about as an owner of this generation:

• Rupturing VVT-i Oil Line (Bank 1) 🔴 High — Common on early models (pre-2010) that have not had the updated all-metal line installed. Failure is sudden and can cause catastrophic engine seizure from oil loss. (Ref: Limited Service Campaign (LSC). The original rubber/metal hose should be replaced with the all-metal line (P/N 15772-31030).)
• Water Pump Failure 🟠 Medium — The water pump is a known wear item, often failing between 80k-140k miles. It typically gives warning with a grinding/whining noise or a small coolant leak from the weep hole before total failure.
• Timing Cover Oil Leak 🟠 Medium — A slow but persistent oil leak can develop from the sealant on the timing chain cover. It's not an immediate threat but is very labor-intensive and expensive to repair properly.
• Melting / Sticky Dashboard 🟡 Low — Common in high-heat, high-humidity climates. The dashboard material degrades, becoming shiny and sticky, which can cause a dangerous glare. While the Highlander was not on the official list for the ZE6 Warranty Enhancement Program, many other Toyotas of the era were, and the issue is known to affect Highlanders. (Ref: ZE6 (for other Toyota models))
• VVT-i Cam Gear Rattle on Cold Start 🔴 High — Primarily affects early 2GR-FE engines (approx. 2008-2009). A loud, brief rattle on cold starts indicates failing cam phasers. If ignored, it can lead to major engine damage. (Ref: T-SB-0087-09 (related))

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: It is strongly discouraged to buy a used ignition coil for this repair. The part is a known failure item, and a used coil from a junkyard has an unknown history and is likely to have a short remaining service life. The low cost of a new, quality aftermarket part makes it the far more sensible choice.

Donor-vehicle mileage cap: roughly under 15000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• Verify the part number on the used coil is one of the later revisions (e.g., 90919-A2007 or newer).
• Inspect the plastic housing for any cracks, melting, or signs of heat stress.
• Check the electrical connector for corrosion or broken locking tabs.
• Avoid parts from vehicles with obvious signs of engine fire or flood damage.

Aftermarket brands forum-validated for this vehicle:

• Denso (Original Equipment Manufacturer)
• NGK
• Hitachi
• Bosch

Brands owners have reported issues with on this vehicle:

• Generic, unbranded ignition coils from online marketplaces without a warranty or clear return policy. While they may be cheap, they have a high rate of premature failure.

Real Owner Stories

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

Documented NHTSA Reports

Related OBD-II Codes

• P0354 — This code identifies an ignition coil circuit issue on Cylinder #4; it is the code that will appear if you swap a faulty Cylinder #2 coil to the middle position for testing.
• P0351 — Identifies an ignition coil circuit issue on Cylinder #1; often appears alongside P0352 during multi-coil failures on high-mileage 2GR-FE engines.
• P0353 — Identifies an ignition coil circuit issue on Cylinder #3; part of the same ignition system failure pattern seen in this engine family.
• P0355 — Identifies an ignition coil circuit issue on Cylinder #5; frequently triggered simultaneously with P0352 in total system stalls.

Frequently Asked Questions