INFINITI G37 (2008-2013) Brake Light Switch: A Guide for Owners
Solve common starting problems, dead batteries, and brake light issues by understanding this critical part.
- Before replacing the switch, check for a broken or missing plastic stopper on the brake pedal arm, as this is a common and simpler problem.
- A bad switch can prevent your G37 from starting, cause poor acceleration, or keep you from shifting out of park.
- The correct part is the 4-pin switch above the brake pedal; the 2-pin switch is for cruise control.
- Proper installation and adjustment are crucial; an incorrectly adjusted switch will not work correctly.
Is It the Switch or Something Simpler?
Check This First! Before you replace the brake light switch, inspect the brake pedal arm for a small plastic or rubber stopper. This stopper presses the switch's plunger. Over time, these stoppers can become brittle, crack, and fall out. If this happens, the switch plunger is never pressed, making the car think the brakes are always on. This leads to brake lights that won't turn off and a drained battery. A missing stopper is a very common issue and a much cheaper fix than a new switch.
Symptoms of a Failing Brake Light Switch
A bad or misadjusted brake light switch on a G37 can cause a surprising number of problems. Because the switch is tied to the ignition and safety systems, you might experience more than just light issues.
- Car Won't Start: You press the brake and push the ignition button, but the engine doesn't crank. The car may only go into accessory (ACC) mode. This happens because the computer doesn't get the signal that the brake is applied, 🎬 See how a faulty switch prevents your G37 from starting. which is a requirement for starting.
- Brake Lights Stay On: The switch can fail in the 'on' position, leaving your brake lights illuminated even when the car is off. This will drain your battery.
- Brake Lights Don't Work: The switch can fail in the 'off' position, meaning your brake lights never come on. This is a critical safety hazard.
- Can't Shift Out of Park: The safety interlock that prevents you from shifting out of Park without the brake applied will not disengage.
- Reduced Engine Power: The car may enter a 'limp mode' with sluggish acceleration because the computer thinks the brakes are being applied and reduces engine power as a safety precaution.
- Dashboard Warning Lights: A faulty switch can trigger ABS, VDC, or SLIP lights on your instrument cluster.
Choosing the Right Aftermarket Brake Light Switch
When replacing the brake light switch, you have options ranging from budget-friendly to premium aftermarket. While an OEM switch from Infiniti/Nissan is one route, several aftermarket brands offer quality alternatives. One owner reported an issue where a cheap aftermarket part's electrical connector did not fit properly, so be mindful of very low-cost options.
Your G37 has two switches above the brake pedal. The brake light switch is the one with a 4-pin electrical connector. The other switch, typically with a 2-pin connector, is for the cruise control.
Brand Tiers
- Premium Aftermarket (e.g., Standard Ignition, Beck Arnley, Vemo): These brands are often trusted by professional shops and are designed to meet or exceed OEM specifications. They are a solid choice for reliability and fitment.
- Mid-Grade Aftermarket (e.g., Dorman, Holstein, Facet): These brands offer a good balance of price and quality. Dorman is well-known for providing solutions to common OEM problems.
- Value-Oriented (e.g., Replacement, True Tech, URO Parts): These are typically the most affordable options. While they can be a good value, it's important to verify fitment and be aware that build quality may not be as robust as higher-priced alternatives.
| Part Type | Price Range |
|---|---|
| New Aftermarket | $24.01 - $67.91 |
| New OEM (Dealer) | $45 - $70 |
| Shop Labor | $50 - $100 |
Known Issues, Recalls, and TSBs
As of late 2024, there are no specific recalls or Technical Service Bulletins (TSBs) from INFINITI or the NHTSA for the brake light switch on the 2008-2013 G37. However, the failure of the switch and the related pedal stopper pad is a widely documented issue among owners in online forums.
Frequently Asked Questions (FAQ)
Why won't my G37 start and just goes into ACC mode?
This is a classic symptom of a bad brake light switch. The car's computer doesn't receive the signal that the brake pedal is pressed, which is a required safety step to start the engine. Before replacing the switch, check that your brake lights are working. If they are not, the switch is the most likely culprit.
Why are my brake lights stuck on and draining my battery?
This can be caused by two things: a failed brake light switch stuck in the 'on' position, or a disintegrated plastic stopper on the brake pedal arm. The stopper is meant to press the switch's plunger when your foot is off the brake. If the stopper is gone, the plunger is never pressed, and the lights stay on. Always check for the stopper first.
Is replacing the brake light switch a DIY job?
Yes, for most people with basic tools, this is a straightforward DIY repair. The switch is located above the brake pedal and can be removed by disconnecting the electrical plug and twisting the switch to unlock it from its bracket. 🎬 Watch this video for a quick walkthrough on replacing the switch. The most difficult part is the uncomfortable position required to work under the dashboard.
How do I adjust the new brake light switch?
Proper adjustment is critical. The switch has a threaded body. It must be installed so that the plunger is fully depressed when the brake pedal is at rest, but is released as soon as the pedal is pressed even slightly. An improperly adjusted switch will cause the same symptoms as a broken one.
Helpful Videos
Technical Specifications
OEM Part Numbers: 25320-9AE0A 25320-AX000 25320-AX00A 25320-AX00B 25320-AX00C 25320-AX00E 25320-AX10A
4-pin electrical connector, push-type switch, threaded body for adjustment.
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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.
- INFINITI G37: