Ram 4500 Brake Light Switch Guide: Symptoms and Replacement for 2011-2018 Models
Is your cruise control acting up or are your brake lights on the fritz? Your brake light switch might be the culprit.
- A faulty brake light switch often causes cruise control failure and can trigger ABS/traction control lights on the dash.
- Check your VIN for safety recall NHTSA 18V-100, which affects the related Brake Transmission Shift Interlock on 2017-2018 models.
- Replacement is a simple DIY task that takes less than 30 minutes and requires no special tools.
- Choose a quality aftermarket brand like Standard Ignition or Rostra to avoid premature failure and repeat repairs.
Is Your Ram 4500 Brake Light Switch Failing?
A failing brake light switch on a heavy-duty truck like the Ram 4500 is a safety issue that needs immediate attention. Because this switch talks to so many different systems, symptoms can be varied and sometimes confusing. Recognizing them early can save you from a failed roadside inspection or a potential accident.
Common Failure Symptoms:
- Brake Lights Don't Work: The most obvious and dangerous symptom is when your brake lights fail to illuminate when you press the pedal.
- Brake Lights Stay On: The switch can fail in the 'on' position, leaving your brake lights constantly illuminated. This can drain your battery and confuse other drivers.
- Cruise Control Won't Engage: If the switch is faulty, it may incorrectly tell the truck's computer that the brakes are being applied, preventing the cruise control from turning on or causing it to shut off unexpectedly.
- Can't Shift Out of Park: The Brake Transmission Shift Interlock (BTSI) requires a signal from the brake switch to allow the gear selector to move out of Park. If the signal isn't received, your shifter will be stuck. 🎬 See how to fix a truck that won't shift out of park.
- ABS and Traction Control Lights: A faulty switch can trigger warning lights for the Anti-lock Brake System (ABS) or Electronic Stability Control (ESC) on your dashboard.
- Check Engine Light: A failing switch can trigger diagnostic trouble codes (DTCs) such as P0571, P0572, P0573, or P0703. 🎬 Watch: How to fix a P0703 code on your Ram.
Important Recall Information for 2017-2018 Ram 4500/5500
FCA issued a safety recall (NHTSA 18V-100 / FCA U11) for some 2017-2018 Ram 4500/5500 trucks for a problem with the Brake Transmission Shift Interlock (BTSI). This could allow the truck to be shifted out of Park without pressing the brake pedal, creating a rollaway risk. While this isn't a recall on the brake light switch itself, the function is directly related. An ongoing NHTSA query (RQ25003) is investigating the effectiveness of this recall. It is critical to check if your truck's VIN is affected by visiting the NHTSA website.
Choosing the Right Aftermarket Brake Light Switch
When replacing the brake light switch, you have options ranging from budget-friendly to premium aftermarket. For a critical safety component, quality and reliability should be the priority.
- Premium Aftermarket (Standard Ignition, Rostra): Brands like Standard Ignition (SMP) have a long-standing reputation for producing quality electrical components that often meet or exceed OEM standards. Rostra is another solid choice, specializing in vehicle electronics and testing their parts for performance and reliability. These brands are often preferred by professional mechanics for their dependability.
- Value Aftermarket (Dorman): Dorman is a well-known brand that offers a wide range of parts. While often more affordable, experiences can be mixed. It's a viable option, but ensure you are buying the correct part for your application.
- Brands to be Cautious With (Crown Automotive, Vemo): Crown Automotive is heavily focused on the Jeep market, and reviews for parts on other vehicles can be inconsistent, with some users reporting fitment issues on non-Jeep applications. Vemo is a European-centric brand and may be less common for Ram trucks in the North American market. For a critical part like this, sticking to a more proven brand for your truck is recommended.
Common Ordering Mistake
Be careful when ordering. For example, the Dorman part number 924-738 is often associated with this repair but it is actually a shift park release link for the shifter mechanism, not the electronic brake light switch located at the pedal. Always verify the part description and appearance before purchasing.
Cost of Replacing a Ram 4500 Brake Light Switch
This is an inexpensive and straightforward repair, especially if you do it yourself.
| Item | Estimated Cost |
|---|---|
| New OEM Mopar Switch | $40 - $58 |
| New Aftermarket Switch | $21 - $43 |
| Shop Labor | $50 - $100 |
| DIY Total | $21 - $43 |
| Shop Repair Total | $71 - $158 |
Frequently Asked Questions (FAQ)
Is replacing the brake light switch a DIY job?
Yes, absolutely. The switch is located above the brake pedal arm and is held in place by tabs. The replacement involves disconnecting the wire harness, twisting the old switch to remove it, and then twisting the new one into place. It typically requires no special tools, though a small pry tool or flathead screwdriver can help with the electrical connector. The job can usually be done in under 30 minutes.
Should I buy an OEM Mopar switch or is aftermarket okay?
While OEM Mopar parts are always a safe bet, a high-quality aftermarket switch from a reputable brand like Standard Ignition or Rostra is a reliable and cost-effective alternative. Some forum users have reported immediate failures with lower-quality aftermarket switches, so it's wise to avoid the cheapest options.
How do I know it's the switch and not a fuse or the bulbs?
Always check the simple things first. Verify that the brake light fuse is not blown and that the brake light bulbs themselves have not burned out. However, if you are also experiencing other electronic issues like cruise control failure or a shifter that's stuck in park, the brake light switch is the most likely culprit as it is the common link between all these systems.
My new switch is installed, but it's not working. What now?
First, ensure the electrical connector is fully seated. Some switches also require a self-adjustment or calibration step. A procedure mentioned by some owners involves installing the new switch, pulling the brake pedal fully rearward, and then pushing it forward until it stops to properly set the plunger depth. 🎬 Watch this guide on calibrating your new brake switch sensor. If problems persist, you may have received a defective part, which is more common with lower-tier brands.
Helpful Videos
Technical Specifications
OEM Part Numbers: 68078700AE 4671336AD 56038914AA 4671336AB 68078700AC
Located on the brake pedal support bracket under the driver's side dashboard. It is a plunger-style switch that is activated by the movement of the brake pedal arm.
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.
- Ram 4500:
- 🎬 Helpful Videos
- 🛍️ Shop This Part
- Is Your Ram 4500 Brake Light Switch Failing?
- Common Failure Symptoms:
- Important Recall Information for 2017-2018 Ram 4500/5500
- Choosing the Right Aftermarket Brake Light Switch
- Common Ordering Mistake
- Cost of Replacing a Ram 4500 Brake Light Switch
- Frequently Asked Questions (FAQ)
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