1937-1939 Nash LaFayette Brake Light Switch Guide
Keeping the brake lights on your classic Nash working is a critical safety task.
- The 1937-1939 Nash LaFayette uses a hydraulic pressure brake light switch, not a mechanical one.
- Failure is a critical safety issue; either your brake lights won't work or they will get stuck on.
- Replacement is straightforward but requires bleeding the brakes afterward.
- A modern aftermarket part from a brand like Standard Ignition is a more reliable choice than a rare, aged original part.
Symptoms of a Failing Brake Light Switch
On a vintage car like the Nash LaFayette, brake light switch problems are common and pose a serious safety risk. The most obvious signs of failure are brake lights that don't turn on at all when you press the pedal, or brake lights that stay on constantly, even when the car is parked. The latter can drain your battery overnight. You might also see flickering brake lights, which could point to a switch that is failing internally or has a bad connection. Since these older hydraulic switches can be sensitive, they may require a very firm press on the pedal to activate if they are starting to wear out.
Warning: Driving without functional brake lights is extremely dangerous and illegal. A faulty switch means drivers behind you have no warning you are stopping, which can easily lead to a rear-end collision. Address this issue immediately.
🎬 Watch this guide on brake light switch symptoms and costs.Choosing The Right Aftermarket Part
For a 1937-1939 Nash LaFayette, finding an original "New Old Stock" (NOS) brake light switch is nearly impossible. Even if you found one, the internal rubber diaphragms could be degraded from decades of storage, making it unreliable. A modern aftermarket replacement is the most practical and reliable choice.
These cars used a simple hydraulic switch that was common on many vehicles from the 1930s to the 1960s. Aftermarket manufacturers produce replacements that meet or exceed the original specifications.
- Standard Ignition: Standard Ignition is a well-known brand that produces reliable replacement electrical parts. Their hydraulic brake light switches are designed as direct replacements. They use modern materials to offer a longer service life than the original switches, which were known to fail. The Standard Ignition SLS22 is a common replacement for this type of application.
Pro Tip: Many classic car owners report that modern reproduction hydraulic switches can fail prematurely, sometimes due to the amperage load of original incandescent bulbs. Some owners install a relay to reduce the electrical load on the switch itself, while others convert to a more reliable mechanical switch, though this requires custom fabrication.
Estimated Replacement Costs
The cost to replace the brake light switch on your LaFayette is reasonable, but it's important to factor in potential related tasks.
| Item | Estimated Cost |
|---|---|
| New Aftermarket Switch | $38.97 |
| Shop Labor | $100 - $200 |
| Total Estimated Cost | $139 - $239 |
Note: Prices are estimates and can vary based on your location and the specific needs of your vehicle. The job requires bleeding the brakes, which is included in the labor estimate.
Frequently Asked Questions (FAQ)
Can I replace the brake light switch myself?
Yes, this is a DIY-feasible job for someone with experience working on vintage car brake systems. The switch simply unscrews from its port. However, you must be prepared to bleed the brake system afterward to remove any air that enters the lines. Have a new container of the correct type of brake fluid ready.
Why do these hydraulic switches fail so often?
Hydraulic pressure switches on classic cars are a known weak point. The internal diaphragm can harden, leak, or rupture over time. Contamination in the brake fluid can also clog the small orifice in the switch. The electrical contacts can also burn out from the current drawn by the brake light bulbs.
Is there a recall or TSB for the brake light switch on my Nash?
No. Modern databases like the NHTSA do not contain recall or Technical Service Bulletin (TSB) information for vehicles from this era. All maintenance is based on general service knowledge and owner experience.
What is the difference between a hydraulic and a mechanical switch?
Your LaFayette uses a hydraulic switch that is activated by brake fluid pressure. Most modern cars use a mechanical switch that is physically activated by the movement of the brake pedal arm. Some classic car owners modify their vehicles to use a mechanical switch because they are often more reliable and do not require opening the hydraulic system to replace.
🎬 Learn how to install a mechanical switch in classic cars.Helpful Videos
Technical Specifications
Hydraulic Pressure Activated, 2-Terminal
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.