2021-2025 Toyota Camry and Other Models Acid Rain Damage TSB

Toyota has issued Technical Service Bulletin (TSB) T-SB-0035-24, which addresses the prevention and repair of acid rain damage on vehicle paint finishes. This bulletin, revised on April 19, 2024, supersedes Service Bulletin No. B091-020, which is now obsolete. The updated TSB includes applicability for 2025 model year 4Runner Hybrid and Crown Signia vehicles.

Acid rain damage is a common concern for vehicle owners, and this TSB provides comprehensive guidance for technicians to restore affected paintwork. The procedures are intended for use by qualified body/paint technicians and should not be attempted by inexperienced personnel.

Symptoms of Acid Rain Damage

Acid rain results from rainwater or airborne moisture that becomes acidic due to industrial chemical impurities. When these acidic compounds settle on exposed vehicle surfaces, especially horizontal areas like the hood, roof, and decklid, they can cause significant damage to the painted finish. Owners typically identify acid rain damage by the presence of stains on the paint surface that resemble hard water spots. However, unlike water spots, acid rain damage cannot be removed by regular washing.

Acid rain can etch and soften the paint, making normal buffing or polishing repair procedures ineffective and potentially causing further damage or visible depressions in the paint surface. The bulletin categorizes acid rain damage into three types:

• Minor damage: Typically requires only buffing for repair.
• Moderate damage: Usually necessitates neutralizing, color sanding, and buffing.
• Severe damage: Extends beyond 1/2 mil of clearcoat on pearl, metallic, or solid colors, requiring neutralization, sanding, and repainting.

Important Warnings for Owners and Technicians

Toyota emphasizes several critical points regarding acid rain damage repair:

• Matte Paint Finishes: "The following process can be followed but with matte paint finish safe products ONLY. Using materials listed in this document can lead to paint damage to matte paints."
• Buffing Procedures: "To minimize the possibility of burning through or hazing paint surfaces, the following buffing procedures should be performed only by personnel experienced in rotary power buffing." Additionally, "Use only LIGHT pressure on the buffer to prevent burn-through damage to the paint surface."
• Sanding Precautions: "While it is recommended to sand down into the primer coat, the underlying electro deposition coat should NOT be exposed, since it provides essential corrosion protection."
• Paint Type: "lacquer-type paint is NOT recommended for this application" for severe damage repair.
• Chemical Disposal: "Check with state and local ordinances regarding the use and disposal of all chemicals."

Repair Procedure Summary

The TSB outlines specific repair procedures based on the severity of the acid rain damage. All procedures begin with moving the vehicle out of direct sunlight to cool the paint surfaces and thoroughly washing the vehicle with automotive liquid soap and water.

Minor Damage Repair

For minor acid rain damage, the process involves neutralizing any remaining acid with a baking soda solution applied via a commercial-grade plastic garden sprayer, followed by a thorough rinse. Technicians then measure paint film thickness in several locations before buffing the affected areas using the least aggressive pads and liquid compounds. Paint film thickness is continuously monitored during buffing to prevent excessive material removal. Very lightly affected areas may also be buffed using 3M™ Perfect-It™ System or equivalent products.

Moderate Damage Repair

Moderate damage requires similar initial steps of cooling, washing, and neutralizing. However, this level of damage also includes color sanding using #1500 or #2000 grit wet-dry sandpaper with a soft foam rubber sanding pad. Technicians must frequently apply clean water and wipe down sanded areas to check for spot removal. Continuous measurement of paint film thickness is crucial throughout the sanding process, ensuring no more than 1/2 mil of clearcoat is removed on pearl, metallic, or solid colors. After sanding, the area is buffed to achieve a high-gloss finish.

Severe Damage Repair

When acid damage has penetrated more than 1/2 mil on metallic, pearl, or solid color paint after color sanding, severe damage repair is necessary. This involves washing, rinsing with deionized water, and cleaning affected areas with appropriate silicone/wax remover (such as DuPont 3939, PPG DX330/DX380). A dual-action sander is used to eliminate any depressions, sanding down into the primer coat without exposing the electro deposition coat. After finishing sanding with wet-dry sandpaper and re-cleaning, a quality urethane enamel color coat or base coat/clear coat is applied as required for maximum repair durability. Lacquer-type paint is not recommended for this application.

Required Tools or Parts

To perform these repairs, technicians will need specific tools and materials, including:

• Liquid Automotive Washing Soap, Baking Soda, Water Pail
• 3M™ Finesse-It™ II Machine Polish (or Equivalent)
• 3M™ Perfect-It™ System (or Equivalent)
• 3M™ Finesse-It™ II Wool Pad (or Equivalent)
• 3M™ Perfect-It™ Foam Pad (or Equivalent)
• #1500 or #2000 Grit Wet-Dry Sandpaper Pre-Soaked in Clean Water
• Variable Speed Rotary Buffer, Speed Range 1200–1800 rpm
• Elcometer® 211 Mechanical Coating Thickness Gauge, Magnetic (or Equivalent)
• Fischer® Deltascope DMP30, Digital (or Equivalent)

Owner Action

If you observe acid rain damage on your 2021-2025 Toyota Camry or other applicable Toyota model, it is recommended to contact your authorized Toyota dealership. They have access to this Technical Service Bulletin and the necessary specialized tools and trained personnel to properly diagnose and repair the damage according to Toyota's guidelines. Addressing acid rain damage promptly can prevent further deterioration of your vehicle's paint finish and maintain its aesthetic appeal and resale value.

NHTSA ID: 11007443