1. What is P0355 in Toyota Camry?

The P0355 OBD-II code stands for Ignition Coil A Primary/Secondary Circuit Malfunction. For the Toyota Camry (2018-2024)—America’s best-selling sedan—this code targets the Ignition Coil A in the 2.5L Dynamic Force 4-cylinder engine (standard in LE, XLE, SE, and XSE trims). Ignition coils convert the battery’s 12V power to 40,000+ volts to ignite fuel in the cylinders; Coil A specifically powers the 1st cylinder—critical for smooth idle, acceleration, and fuel efficiency (up to 41 MPG highway).

The Camry’s ECM (Engine Control Module) monitors voltage flow to Ignition Coil A. P0355 triggers when the ECM detects irregular current—signaling a faulty coil, damaged wiring, or bad electrical connection. This is a top issue for 2019-2023 Camry 2.5L models, as Toyota’s TSB (Technical Service Bulletin) 21-007 notes: the 2.5L’s high-compression design (13:1) puts extra stress on ignition coils, leading to early failure (typically around 80,000–100,000 miles).

2018-2024 Camry Specific Note: Ignition Coil A is located on the 1st cylinder (passenger-side front of the engine). LE and SE trims—used mostly for daily commuting—are more prone to P0355. Stop-and-go driving cycles the coil frequently, while short trips prevent the engine from reaching optimal operating temperature, accelerating coil wear.

2. Common Causes of P0355 in 2018-2024 Camry

P0355 in Camry 2.5L models is almost always tied to coil wear or electrical issues—below are real-world cases diagnosed with the ICARZONE UR800:

• Aged Ignition Coil A (2020 Camry LE 2.5L): An LE owner with 95,000 miles reported rough idle and misfires. The UR800’s Ignition Coil Voltage Test showed 0.2V (normal: 11.5–12.5V) to Coil A. The coil’s internal windings failed (per TSB 21-007)—replacing it with OEM #90919-C2007 fixed P0355.
• Loose Coil Connector (2021 Camry SE 2.5L): An SE owner’s P0355 came and went with bumps. The UR800’s Circuit Continuity Test found intermittent resistance (15Ω, then 0.3Ω). The Coil A connector was loose—resecuring it and applying dielectric grease eliminated the fault.
• Damaged Coil Wiring (2019 Camry XLE 2.5L): An XLE owner’s P0355 persisted after coil replacement. The UR800’s Wiring Fault Scan revealed a frayed wire in the Coil A harness (rubbed against the valve cover). Splicing the wire with heat-shrink connectors (#Dorman 84731) restored voltage flow.
• Bad ECM Driver (2022 Camry XSE 2.5L): An XSE owner’s P0355 wouldn’t clear. The UR800’s ECM Output Test showed the ECM wasn’t sending power to Coil A. Updating the ECM firmware via UR800’s "Toyota Calibration" tool fixed the driver issue (addressed in TSB 22-003).

3. Key Symptoms of P0355 in Camry 2.5L

P0355 symptoms in the Camry are hard to miss—they directly affect engine performance, especially during acceleration. Watch for these signs:

4. Camry Trims/Engines Prone to P0355

Toyota service records and owner forums confirm P0355 is most common in these 2018-2024 Camry configurations (all 2.5L Dynamic Force 4-cylinder):

5. Diagnose P0355 with ICARZONE UR800

Diagnose P0355 in your Camry 2.5L accurately with the UR800’s Toyota-specific ignition tools. Follow these steps (engine off, key in "ON" position):

Case Example: A 2020 Camry LE failed Step 2 (9.8V) and Step 4 (1.5Ω). The UR800’s Component Location Tool guided Coil A access (remove engine cover, 4 plastic clips). Replacing the coil with OEM #90919-C2007 fixed P0355—verified by test drive (smooth idle, no misfires).

6. How to Fix P0355 in Camry 2.5L

Resolve P0355 in your Camry with these UR800-verified solutions—tailored to the 2.5L Dynamic Force engine:

1. Replace Faulty Ignition Coil A (Most Common Fix)

1. Confirm coil failure via UR800’s Step 4. Disconnect the negative battery terminal for safety.
2. Remove the engine cover: Pull up gently (4 plastic clips) to access the ignition coils (4 coils, left to right: A, B, C, D).
3. Locate Ignition Coil A (passenger-side front coil). Disconnect its electrical connector (press the tab) and remove the 10mm mounting bolt.
4. Pull the coil straight up to remove it (use a slight twisting motion if stuck). Inspect the coil boot—replace if cracked (prevents moisture damage).
5. Install an OEM Ignition Coil A:
   • 2018-2021 Camry: #90919-C2007
   • 2022-2024 Camry: #90919-C2015 (updated heat-resistant design)
6. Reinstall the mounting bolt (torque to 89 in-lbs), reconnect the connector and battery. Clear P0355 with UR800 and test drive for 10 miles.

2. Repair Damaged Coil A Wiring

1. Confirm wiring damage via UR800’s Step 3. Locate the frayed/broken wire in the Coil A harness (near the valve cover).
2. Cut the damaged section (1 inch on each side of the fault) and strip 1/4 inch of insulation from the wire ends.
3. Splice the wires with heat-shrink butt connectors (#Dorman 84731) and crimp firmly with a wire crimper.
4. Heat the connectors with a heat gun to seal the shrink tubing—ensure no exposed wire remains.
5. Secure the repaired harness to the engine with zip ties (away from hot surfaces). Retest continuity with UR800, clear P0355, and verify performance.

3. Update ECM Firmware (TSB 22-003)

1. Confirm TSB eligibility via UR800’s Step 5. Ensure the Camry is parked in a well-ventilated area (update takes 15–20 minutes).
2. Connect the UR800 to the OBD-II port and select "Toyota" > "Camry" > "ECM" > "Firmware Update."
3. The UR800 will detect the current ECM version and download the latest update (matches TSB 22-003 specs).
4. Do not turn off the engine or disconnect the UR800 during the update. The tool will alert you when complete.
5. Restart the engine, clear P0355, and run the UR800’s voltage test again—ensure Coil A gets 11.5–12.5V.

7. P0355 Repair Costs & Maintenance Tips

P0355 repair costs for the Camry 2.5L are affordable—here’s a breakdown for DIY and professional work:

Maintenance Tips for Camry 2.5L Owners

• Replace Ignition Coil A every 80,000 miles (preventive) — follow TSB 21-007 and use OEM coils (aftermarket coils fail 2x faster in the 2.5L engine).
• Change spark plugs every 60,000 miles (use OEM iridium plugs #90919-C2005). Worn plugs strain ignition coils, leading to P0355.
• Inspect Coil A’s connector during oil changes — apply dielectric grease to the pins annually to prevent corrosion (critical in humid climates).
• Avoid short trips (under 5 minutes) when possible. Longer drives let the engine reach optimal temperature, reducing coil stress.
• Perform the UR800’s Ignition System Health Check every 15,000 miles — monitor coil voltage and resistance to catch issues before P0355 triggers.

8. Camry-Specific FAQs