A Guide to the Brake Light Switch for the 2016 Scion iM
Understanding the symptoms of a failing brake light switch and how to choose the right replacement for your iM.
- A failing brake light switch can cause more than just brake light problems; it can also prevent your car from starting or shifting out of Park.
- This is a critical safety component. If your brake lights are not working, the vehicle is unsafe to drive and should be repaired immediately.
- Before assuming the switch is bad, always check the brake light fuse and the bulbs themselves, as these are common and simpler failure points.
- Replacement is a simple DIY task for most owners, located just above the brake pedal arm.
Is Your Brake Light Switch Failing?
A faulty brake light switch can cause several confusing issues that might not seem related to the brakes at first. Because the switch is involved in multiple vehicle systems, its failure can be a serious safety concern and prevent your car from operating correctly. Recognizing the signs early can save you from a roadside headache or a potential accident.
Common Symptoms of a Bad Switch
🎬 See a visual guide to common bad switch symptoms.- Brake Lights Don't Work: The most obvious sign is when your brake lights do not illuminate when you press the brake pedal. This is a critical safety failure.
- Brake Lights Stay On: The switch can also fail in the 'on' position, causing the brake lights to remain lit even when you're not braking. This can confuse other drivers and will drain your battery.
- Cannot Shift Out of Park: Your iM has a safety feature called a shift interlock that requires you to press the brake before shifting. If the switch is bad, the system won't get the signal, and your gear shifter will be stuck in Park.
- Cruise Control Issues: If the cruise control won't engage or shuts off unexpectedly, it could be due to a faulty brake light switch sending an incorrect signal.
- Car Won't Start (Push-Button Start): The push-to-start system needs to confirm the brake is pressed before it will allow the engine to crank. A bad switch will prevent this, leaving you with a no-start condition.
Pro Tip: Check the Basics First
Before you replace the switch, always check for simpler issues. A blown fuse or burnt-out brake light bulbs can cause similar symptoms. Consulting your owner's manual for the correct fuse location can be a quick first diagnostic step.
Choosing the Right Aftermarket Brake Light Switch
For the 2016 Scion iM, the original equipment (OEM) switch is a reliable choice, but quality aftermarket options can offer comparable performance at a better price. Aftermarket brands can generally be grouped into tiers based on reputation and quality.
Brand Quality Tiers
- Premium Aftermarket (Good): Brands like Beck Arnley and Standard Ignition (SMP) have a strong reputation. Beck Arnley is well-regarded for sourcing parts that meet or exceed OEM specifications for Japanese vehicles, and sometimes even re-boxes the original part.
- Standard Aftermarket (Better): Brands such as Vemo and Holstein fall into this category. They are dependable replacements for daily driving, though specific reviews for this part are limited. They offer a balance of price and quality.
- Economy (Basic): Brands listed as Replacement or True Tech are typically budget-focused options. While they are the most affordable, they may not offer the same longevity or precise fit as higher-tiered brands.
Safety First
Driving with a faulty brake light switch is dangerous. If your brake lights are not working, you are at a much higher risk of being rear-ended. It is also illegal and will cause you to fail a safety inspection. This repair should not be delayed.
Cost of Replacing the Brake Light Switch
The cost to replace the brake light switch is relatively low. The part itself is inexpensive, and labor is minimal due to its easy access. Below is a general cost estimate.
| Part Type | Estimated Cost |
|---|---|
| New Aftermarket | $24.19 - $39.30 |
| New OEM | $40 - $65 |
| Shop Labor | $50 - $100 |
Frequently Asked Questions
Are there any recalls for the 2016 Scion iM brake light switch?
No. As of early 2026, there are no active recalls or technical service bulletins (TSBs) from the NHTSA specifically for the brake light switch on the 2016 Scion iM.
How difficult is it to replace the brake light switch myself?
The replacement is considered easy and is very feasible for a DIY mechanic. It is located above the brake pedal and typically requires no special tools—just unplugging the electrical connector and twisting the switch to remove it. The most difficult part is often the awkward position required to work under the dashboard.
🎬 Watch: Step-by-step guide to replacing the switch yourself.Can a bad brake light switch really drain my car's battery?
Yes. If the switch fails in the closed or 'on' position, it will cause your brake lights to stay on constantly, even when the car is off. This parasitic draw will drain the battery, potentially leaving you unable to start the car.
Why won't my car shift out of Park? Is it the brake light switch?
It is a very common cause. The shift interlock solenoid needs a signal from the brake light switch to release the gear selector from Park. If the switch is faulty, the solenoid won't activate, and your shifter will be stuck.
🎬 Watch: How to fix a car stuck in Park.Helpful Videos
Technical Specifications
OEM Part Numbers: 84340-09310 84340-19025 84340-19026 84340-09040 84340-09070 84340-79015 84340-09041
Located on the brake pedal support bracket, this is a plunger-style switch that completes an electrical circuit when the brake pedal is depressed.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Scion iM: