Skip to content
Diagnostic tests 2026 firmware

Trailer Light Controller (TLC) - Test If Connected

Model3/tasks/TEST_VCLEFT-TLC_REAR_TRAILER-CONTROLLER-CONNECTED

Model 3 / Y

What this task does

Tests whether the Trailer Light Controller (TLC) load is connected to the left vehicle controller (VCLEFT) ECU.

Vehicle & firmware coverage

Open a version to see its description, requirements, and input definitions. Hardware configuration and live vehicle checks also determine availability.

Model 3 / Y AMD · Firmware 2026.32.3
Vehicle coverage
2024+ Model 3, 2025+ Model Y, Model Y, Pre-2024 Model 3
Supported connection
Local connection
Vehicle state
Stationary · Parked
Gateway diagnostic level
No specific level listed

Task inputs (0)

No user inputs are listed in this firmware.

Model 3 / Y Intel · Firmware 2026.32.7
Vehicle coverage
Model Y, Pre-2024 Model 3
Supported connection
Local connection
Vehicle state
Stationary · Parked
Gateway diagnostic level
No specific level listed

Task inputs (0)

No user inputs are listed in this firmware.

Related service tasks

Browse all tasks →
Diagnostic tests

Trailer Light Controller (TLC) LIN Communication Test

Tests communication of the Trailer Light Controller (TLC) Electronic Control Unit (ECU). Communication is established over the Local Interconnect Network (LIN) bus network.

TEST_VCLEFT-TLC_REAR_TRAILER-LIN-COMM

Model 3 / Y Model S / X (2021+)