2021-2023 Tesla Model 3 Brake Line Corrosion & Fluid Loss

Tesla has issued Service Bulletin SB-26-33-001 to address a potential issue with brake line corrosion in certain 2021-2023 Model 3 vehicles. This condition can lead to brake fluid loss, which may trigger a "low brake fluid alert" on the vehicle's display. Owners concerned about a potential Tesla Model 3 brake fluid leak should pay attention to these symptoms.

Important Warnings

Tesla notes that "Due to dual redundancy, vehicle safety is not impacted by corrosion on the brake lines." This means that while corrosion can lead to fluid loss and alerts, the vehicle's overall safety system is designed to mitigate immediate risks.

Symptoms

Owners of affected 2021-2023 Tesla Model 3 vehicles might notice the following:

• A "low brake fluid alert" displayed on the vehicle's instrument cluster.
• Visible evidence of a brake fluid leak.
• Failure of a periodic roadworthiness inspection due to brake system concerns.

These symptoms indicate a potential Tesla Model 3 brake fluid leak or corrosion issue that requires professional attention.

Diagnosis and Trigger Conditions

When a customer reports a "low brake fluid alert," a brake fluid leak, or a failed roadworthiness inspection, technicians are instructed to inspect the brake lines. The presence of corrosion on any of the brake lines is the primary trigger for the corrective action outlined in Service Bulletin SB-26-33-001.

Repair Procedure Summary

The repair, as detailed in Service Bulletin SB-26-33-001, involves a comprehensive inspection of the brake lines. If corrosion is identified on any brake lines, all brake lines on the vehicle are to be replaced with new, corrosion-resistant parts. This is performed as a single, combined repair.

The procedure requires significant disassembly, including the removal of the high voltage battery, front and rear subframe assemblies, and various brake line bundles. New brake lines are then installed, secured, and torqued to specification. The process concludes with bleeding the brakes to ensure proper function. The estimated labor time for this correction is 10.6 hours.

Required Tools or Parts

The repair necessitates a variety of specific parts and special tools to ensure proper completion. Key components include:

• Brake Line Assemblies: PIPE ASSY, BRAKE MCYL TO HCU,LHD, PA COAT; PIPE ASSY FR, BRAKE, MODEL 3, PA COAT; PIPE ASSY, SIDE SILL BRAKE; PIPE ASSY L,RR BRAKE; PIPE ASSY R,RR BRAKE.
• Fasteners: Various bolts and nuts, including BOLT, 5LOBE,M6x19,ZNNI,MAT,PTP,SEAL; BOLT,HF,M14-2.0x120,ZNFL,CMAT; NUT,HF,M10-1.5,ZNNI,PTP.
• Seals and Brackets: SEAL, PERIMETER,PENTHOUSE, MDL3; BRACKET – PLASTIC.

Special tools required for this extensive repair include:

• 3/4 TON UNDERHOIST STAND
• Various socket wrenches (e.g., 3/8-inch TX SKTWRNCH-3/8IN-INTX-TX40, 1/2" DR, 20EP TORX PLUS EXTERNAL)
• ADAPTER, LIFT PAD, MODEL 3
• DIGITAL MULTIMETER, 1000V RATED
• DRILL, 1/2" DR, CORDLESS, 18V
• EXTENSION, 1/4" DR, 6", LOCKING, INSULATED
• TORQUE WRENCHES (e.g., DIG+ANG,1/4"DR, FIXHD, IMPACT; DIGITAL+ANGLE, 3/8" DR, FLEX HEAD)
• VACUUM REFILL TOOL

Shop supplies such as THREADLOCKER, LOCTITE 222, COOLANT, ETHYLENE GLYCOL, and BRAKE FLUID DOW are also specified.

Owner Action

If you own a 2021-2023 Tesla Model 3 and observe a "low brake fluid alert" or suspect a Tesla Model 3 brake fluid leak, it is recommended to contact a Tesla Service Center. While the bulletin states that vehicle safety is not immediately impacted, addressing brake line corrosion proactively is crucial for maintaining your vehicle's braking system integrity.

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Source: NHTSA ID: 11029583, Service Bulletin SB-26-33-001