Vehicle Side 4-Way Trailer Connector Plug-in Circuit Tester Lights Light Up when Connected
Published 09/30/2014
Products Featured in This Question
Question:
When I plugged in the 4 prong trailer tester, all three green lights flashed. What does that indicate?
asked by: Dan F
Expert Reply:
If the lights on a 4-Way trailer connector tester such as # I26 light up when connected that means that those circuits are receiving power. It doesn't take much power to light up these small LED lights so even residual current could set them off. This is typically more likely on aftermarket installed trailer wiring harnesses that have a connection to the battery to power the trailer lights.
It could also indicate a short circuit if the lights stay on all the time. The likely cause is a dirty or corroded trailer connector or damaged wiring with copper strands touching bare metal. I have included some links to the right that should help troubleshoot.
Product Page this Question was Asked From
Featured Help Information
Miscellaneous Media
Continue Researching
- Video: Ultimate Overview of the 2-1/4" Long Torx; Floor Screws, 40/Pkg
- Shop: Trailer Wiring
- Shop: Replacement Self-Tapping Pontoon Deck Screws - Stainless Steel - Qty 100
- Shop: Torx Head Screwdriver Bit
- Shop: 2-1/2" Long Torx Floor Screws, 40/Pkg
- Shop: 2-1/4" Long Torx; Floor Screws, 40/Pkg
- Shop: 2-1/4" Long Torx Trailer Floor and Wall Liner Screw for ACQ Treated Wood
- Shop: 2-1/2" Long Torx Trailer Floor and Wall Liner Screw for ACQ Treated Wood
- Search Results: tire cover 205 75 r15
- Shop: Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Q&A: Troubleshooting Right Tail Light on Trailer that Stays On with Vehicle Ignition Off
- Video: Curt T-Connector Vehicle Wiring Harness Installation - 2019 Toyota Highlander C56217
- Video: A Closer Look at the Hook Probe Circuit Tester
- Video: Checking Out the Curt LED 4-Way Flat Connector (Vehicle End) Tester
- Q&A: How to Determine Correct Trailer Wiring Harness for 2019 Toyota Highlander
- Q&A: How to Determine if a 2019 Toyota Highlander Has a Tow Package
- Q&A: Trailer Running Lights Do Not Work but Brake Lights and Turn Signals Do Work
- Video: Complete Breakdown of the Phoenix USA QuickTrim Hub Cover for Trailer Wheels
- Q&A: Does Replacing Trailer Wiring Connector Require Disconnecting Battery
- Q&A: Adding 7-Way Trailer Connector and Brake Controller to 2015 Toyota Highlander Limited Platinum
- Q&A: Continuous Voltage on Trailer Connector Pins with Ignition Off
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Search Results: trailer hitch
- Shop: Trailer Hitch
- Video: Clean Up Your Trailer Wiring
- Search Results: trailer wiring
- Article: Trailer Wiring Diagrams
- Video: How to Choose a Trailer Brake Controller
- Search Results: trailer tires and wheels
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
on Automotive Tools
