Anderson 4-Way Flat Trailer Connector Tester
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
Anderson 4-Way Flat Trailer Connector Tester
Take the guesswork out of trailer wiring with this simple plug-in tester. It connects directly to the flat 4-way connector on your tow vehicle and uses indicator lights to confirm whether each circuit is working correctly — no multimeter or wiring diagrams required. A quick, reliable way to verify your trailer lighting system before every trip.
Features
- Plugs directly into the tow vehicle's flat 4-way connector
- Indicator lights illuminate to confirm correct electrical connections
- Tests all standard 4-way flat functions: tail lights, left turn/stop, right turn/stop, and ground
- Meets SAE testing standards for flat 4-way trailer connectors
- Compact and easy to store in a tow vehicle or tackle box
Compatible Applications
- Any tow vehicle equipped with a standard flat 4-way trailer connector
- Boat trailers
- Personal watercraft (PWC) trailers
- Utility, cargo, and landscape trailers
- Recreational and equipment trailers
Parts Desk Insights
Best Use Case: This tester is the fastest way to diagnose whether a trailer lighting problem is coming from the tow vehicle connector or the trailer itself. Plug it into the tow vehicle — if the lights illuminate correctly, the vehicle side is good and the fault is in the trailer wiring or lights. If the tester doesn't light up, the issue is at the vehicle connector or fuse. It's an essential tool to keep in your truck for pre-launch checks. If you find a wiring fault, the Anderson 4-Way Wishbone Trailer Wiring Harness Kit is a complete rewire solution, or pick up a 4-Way Flat Trailer Harness 48" Car Side or 4-Way Flat Trailer Harness 48" Trailer Side to replace just the connector that's failing. For connector adapters, see the Seachoice 4-Pole Flat Trailer Connector Set.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 1-3 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.