B3894

Stop Lamp Switch Circuit Plausibility Failure

Severity

⚠️ Medium

Can you drive?

Do not drive — repair immediately

Approx. repair cost

$22–56 (est.)

Symptoms

Brake lights don't work
Error on the dashboard
Incorrect operation of cruise control (if equipped)

Causes

Faulty brake light switch
Open or short circuit in wiring harness
Poor contact in connectors
Problems with the control module

How to Fix

Check the operation of the brake lights
Inspect the brake light switch for mechanical damage
Check the integrity of the wiring harness and contacts
Replace the switch if necessary
Reset the error and check if it returns

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