Complete Trailer Light Wiring and LED Light Replacement for a Towable Air Compressor

Updated 07/20/2026 | Published 06/23/2026

Products Featured in This Question

Optronics LED Trailer Light - Brake, Tail, Turn - Submersible - Round - Red

(1810)

$15.67

Rubber Grommet for 4" Round Trailer Lights - PVC

(237)

$5.01

Right Angle 3-Wire Pigtail for Optronics Trailer Lights - 3-Prong PL-3 Plug - 10" Lead

(694)

$8.70

Question:

I have a air compressor it has two rear grote tail lamps with 3 pin connector. The vehicle connection is 7 pin. No brakes just lite. I would lile to purchase a complete wiring harness and new lites. What do you have available

asked by: Daniel Z

Expert Reply:

Daniel, I'd be happy to help you put together a complete lighting setup.

From your description, it sounds like your towable air compressor uses round Grote-style tail lights with a 3-pin connector. Based on that, I recommend the Optronics LED Trailer Light part # STL43RB along with the matching right-angle 3-wire pigtail part # A47PB. The STL43RB measures 4-5/16 inches in overall diameter and 1-15/16 inches deep, and it's a very common replacement size for this style of trailer light. The grommet that you would need is part # A45GB.

The one thing I'd like to confirm before recommending a complete wiring harness is the style and size of your existing lights. Right now I'm making an educated guess based on what is commonly used on towable air compressors. If your current lights are a different size or mounting style, I'd rather catch that now than have you order the wrong parts. If you can tell me whether the lights are recessed in a rubber grommet or surface mounted, and confirm the diameter of your current lights, I can make sure we're matching the correct components.

Where do you tow the compressor most often, job sites, rural roads, or after dark?

expert reply by: Heather A

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Daniel Z.

6/25/2026

Yes I LOVE THE LED! I have the 7 pin connection on the end No trailer brake or anything else Just the two rear lights

Heather A.

6/25/2026

@DanielZ Thanks, Daniel! That helps. Since you already have a 7-way connector and you're only using the left and right tail lights, we don't need to replace the entire trailer wiring harness. The last thing I need to confirm is the lights themselves. Can you tell me if your current lights are recessed into rubber grommets or if they're surface mounted? Also, if you can measure the diameter of one of the existing lights, I can make sure the Optronics # STL43RB and the # A45GB grommets are the correct fit before you order.

Daniel Z.

6/26/2026

@HeatherA A wiring harness would be great. Do you have a wiring schematic for 7 pin harness

Heather A.

6/26/2026

@DanielZ If you need a new 7-pin wiring harness for the air compressor, you can a trailer end 7-way connector like part # A10-7W8. Here is the wiring configuration for that particular harness. Wire gauge: Brown, red, yellow, and green: 14 AWG Blue: 12 AWG Black and white: 10 AWG Wiring configuration: Brown: passenger side brakes/turn signal Red: driver side brakes/turn signal Green: tail lights Yellow: auxiliary/reverse lights Blue: electric brakes Black: 12V battery charge White: ground I have also attached a help article with the standard wiring schematic for 7-pins. What air compressor do you have, I can help you find the correct wiring. I am not sure what connector you have on your air compressor but this is a A 7-pin SAE plug

Helpful Links

faq-wiring.aspx