M-3157SB Lucas Lighting 3157 Switchback White/Amber High Output CANBUS LED Bulbs – Pair
Lucas Lighting M-3157SB 3157 High Output CANBUS Switchback LED Bulbs – Pair
Upgrade your vehicle's front turn signals and marker lights with the Lucas Lighting M-3157SB 3157 Switchback LED Bulbs. Designed as a direct replacement for standard 3157-style halogen bulbs, the M-3157SB delivers a modern switchback lighting function with a lower-output white running/marker mode and a high-output amber turn-signal mode.
When the vehicle's parking or running lights are on, the bulb illuminates white. When the turn signal is activated, the bulb switches to amber to provide the appropriate turn-signal function. This gives the front of the vehicle a cleaner white appearance during normal operation while maintaining amber turn-signal output when signaling.
The M-Series design uses fewer, higher-power LED chipsets positioned as closely as possible to the original halogen bulb filaments. This helps maintain an effective light-source position within the factory housing while delivering the instant-on response and high-output performance expected from an LED upgrade.
Lucas Lighting also incorporates its latest CANBUS technology into the M-Series to provide compatibility with greater than 90% of vehicles without bulb-out errors or fast-blinking issues. The M-3157SB is sold as a pair of two bulbs.
Key Features
- 3157 Switchback LED Bulbs – Designed for front marker and turn-signal applications
- White Running/Marker Output – Illuminates white during normal running or marker-light operation
- Amber Turn-Signal Output – Switches to amber when the turn signal is activated
- High-Output M-Series Design – Uses fewer, higher-power LED chipsets
- Optimized LED Positioning – LED chipsets are positioned close to the original halogen filament location
- Advanced CANBUS Technology – Lucas states compatibility with greater than 90% of vehicles without bulb-out errors or fast blinking issues
- Instant-On LED Response – LEDs illuminate immediately when activated
- Direct Replacement Design – Designed to replace standard 3157-style halogen bulbs
- Sold as a Pair – Includes two LED bulbs
- Front Turn Signal Application – Designed specifically for switchback marker/turn-signal applications
White Running Light + Amber Turn Signal
The main advantage of the M-3157SB switchback design is its two-stage lighting function.
During normal operation, the bulb provides a white running or marker-light appearance. When the turn signal is activated, the bulb changes to amber, providing the traditional turn-signal color.
This makes the M-3157SB particularly useful for vehicles where the factory front turn signal also operates as a daytime running light or parking/marker light.
The dual-output design provides a lower-output constant mode and a higher-output safety mode for functions such as turn signals.
High-Output M-Series LED Technology
Lucas Lighting designed the M-Series around the importance of LED chip positioning inside the factory lighting housing.
Instead of simply adding a large number of LED chips, the M-Series uses fewer, higher-power LED chipsets positioned as closely as possible to the original halogen bulb filaments. This helps optimize the position of the light source within the factory reflector or housing.
The result is an LED bulb designed to provide a more appropriate light-source position while offering the benefits of LED technology, including instant-on operation.
Advanced CANBUS Compatibility
The M-3157SB incorporates Lucas Lighting's latest CANBUS technology.
Lucas states that the M-Series is compatible with greater than 90% of vehicles without causing bulb-out errors or fast-blinking issues. This makes the M-3157SB a convenient upgrade for many modern vehicles with electronically monitored lighting systems.
Because vehicle electrical systems vary, compatibility cannot be guaranteed for every application. If your vehicle still displays a bulb warning or experiences abnormal operation after installation, additional vehicle-specific troubleshooting or components may be required.
3157 Replacement & Cross-Reference Compatibility
The M-3157SB uses the 3157 bulb style and can replace a wide range of related bulb numbers listed by Lucas Lighting.
Compatible bulb styles include:
3047, 3047K, 3047LL, 3057, 3057A, 3057ALL, 3057K, 3057KLCP, 3057KX, 3057LL, 3057ST, 3057X, 3155, 3155LL, 3157A, 3157AK, 3157K, 3157KX, 3157LL, 3157NA, 3157NAK, 3157NALL, 3157ST, 3157X, 3357, 3357A, 3357ALL, 3357K, 3357LL, 3454NA, 3457, 3457A, 3457AK, 3457ALL, 3457K, 3457NA, 3457NAK, 3757A, 3757AK, 3757ALL, 4057, 4057K, 4057LL, 4114, 4114LL, 4114K, 4157, 4157K, 4157LL, 4157NA, 4157NAK, 5702A, 5702AK
These cross-reference numbers are provided by Lucas Lighting; always verify the original bulb size and application before ordering.
Designed for Front Turn Signal Applications
The M-3157SB is specifically suited to applications where a 3157 bulb performs both a running/marker function and a turn-signal function.
Typical applications include:
- Front turn signals
- Front parking lights
- Front marker lights
- Daytime running light applications where the factory bulb uses a dual-output 3157 configuration
The switchback function is designed for the front of the vehicle, providing white illumination during normal operation and amber illumination when the turn signal is activated.
Direct Replacement Design
The M-3157SB is designed to replace the original 3157-style halogen bulb without requiring a completely different lighting system.
Before installation, confirm that your vehicle uses a 3157 or compatible dual-output bulb in the intended lighting position. Similar-looking bulbs can have different bases, contacts, or electrical functions.
Lucas also notes that a 3157-style bulb can replace a 3156-style bulb, but a 3156 bulb cannot functionally replace a 3157 in applications other than a reverse light.
Quick Specifications
| Specification | Details |
|---|---|
| Brand | Lucas Lighting |
| Series | M-Series |
| SKU | M-3157SB |
| Bulb Type | 3157 LED |
| Function | Switchback |
| Normal/Marker Color | White |
| Turn Signal Color | Amber |
| Output | Dual Output |
| Technology | LED |
| CANBUS | Yes |
| Application | Front Marker / Turn Signal |
| Installation | Direct Replacement |
| Quantity | 2 Bulbs |
| Bulb Style | 3157 |
| Cross-Reference | 3157 and compatible bulb styles |
What's Included
- 2 × Lucas Lighting M-3157SB Switchback LED Bulbs
Important Fitment Information
Before ordering, verify that your vehicle uses a 3157-style dual-output bulb in the specific lighting position where you intend to install the M-3157SB.
The M-3157SB is intended for front marker/turn-signal applications where the factory bulb performs both functions.
Bulb fitment can vary by vehicle year, trim level and lighting position. Lucas Lighting provides a vehicle bulb finder, but recommends verifying the original bulb size because multiple bulb styles may sometimes be available for the same vehicle depending on configuration.
Always compare the original bulb before installation and retain the factory bulbs for reference or emergency use.
Installation
Installation is designed to be straightforward:
- Turn off the vehicle and lighting system.
- Remove the factory 3157 bulb.
- Install the Lucas M-3157SB into the factory socket.
- Verify that the bulb is fully seated.
- Test the running/marker light function.
- Activate the turn signal and verify that the bulb switches from white to amber.
- Check the vehicle dashboard for any bulb warnings or abnormal flashing.
- Reassemble the vehicle once proper operation has been confirmed.
For vehicles with polarity-sensitive LED sockets, verify the bulb orientation if the bulb does not illuminate after installation.
FAQ
Does the Lucas M-3157SB switch between white and amber?
Yes. The M-3157SB is a switchback bulb designed to illuminate white during the normal marker/running-light function and amber when the turn signal is activated.
What vehicles does the M-3157SB fit?
The M-3157SB fits vehicles that use a compatible 3157-style dual-output bulb in the appropriate front marker/turn-signal position. Always verify the original bulb before ordering.
Is the M-3157SB CANBUS compatible?
Yes. Lucas Lighting incorporates CANBUS technology into the M-Series and states that the bulbs are compatible with greater than 90% of vehicles without bulb-out errors or fast-blinking issues.
Will I need load resistors with the M-3157SB?
Lucas designed the M-Series CANBUS system to reduce the need for additional components such as resistors in many applications. However, vehicle electrical systems vary, so some vehicles may still require additional components or troubleshooting.
Is the M-3157SB a white LED bulb?
It is a switchback LED bulb. It illuminates white during its normal running/marker function and changes to amber for the turn signal.
Is the M-3157SB the same as a regular 3157 LED bulb?
No. The M-3157SB is specifically a switchback version of the M-3157. Its dual-output design provides white running/marker illumination and amber turn-signal output.
Can a 3157 replace a 3156?
Lucas states that a 3157 can replace a 3156, but a 3156 cannot functionally replace a 3157 except in a reverse-light application.
How many bulbs are included?
The M-3157SB is sold as a pair and includes two bulbs.