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2-in-1 Circuit Testing Probe Automotive Tool - 12V DC Check Device, 7+4-Pin Truck/RV Trailer Light Accessory, 4-Way Flat Trailer Adapter, 7-Way Connector, Red LED Lights
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$2.47 per sale
UUSADTVerified by GrowiVerified by TikTok Shop84 items- Product price
- $18.99
- Category
- Tools › Diagnostic Tools
- Units sold
- 263 via partner deals
- In stock
- 1,105
- Deal ends
- Jul 24, 2027
- Paid by
- TikTok Shop, directly to you
Product description
Trailer Light Tester 7 Way + 4 Flat, Tests Trailer Circuits Easily on 12V Trucks
This trailer circuit tester is a nice tool to have on hand to check the electrical connections between a tow vehicle and a trailer. Unlike ordinary separate 4-pin or 7-pin testers, this 2-in-1 design allows you to have both 4-pin flat and 7-way blade testers, making it easier for you to use. Simply plug into vehicles tow plug and operate lights, brakes and turn signals to test circuits. When the socket is getting proper power, the tester's various LEDs will light up corresponding to each wire in the connector.
Product Features
Plugs into vehicle-side socket LEDs indicate that each circuit is working
Built-in, red LED lights offer easy troubleshooting and long-lasting use
Speeds trouble shooting time and shows if vehicle is properly wired
Easy and quick to test trailer circuits on most 12V trucks and campers
Please note: Testing your vehicle-side socket is essential after installing a new custom vehicle-to-trailer wiring harness and is highly recommended every time you hitch up to tow.
LED Indicators and Functions
Tips: If LEDs are dim or flicker, check for loose or corroded ground wire. To test the circuit with the tester, use 12V battery charger to determine if LEDs power up.
How to do the Test?
Start vehicle and perform a function test for each of the circuits as listed below:
BU (Back Up) - Shift vehicle into reverse, light should stay on constantly.
BK (Electric Brakes) - Depress brake pedal or press manual override on brake controller, light should stay on constantly.
RT (Right Turn & Stop)- Turn on the right turn signal, light should flash intermittently. Depress brake pedal, light should stay on constantly.
12V (12 Volts+) - Light should be on constantly.
T/M (Taillights) - Turn on headlights, light should stay on constantly.
LT (Left Turn & Stop) - Turn left turn signal on, light should flash intermittently. Depress brake pedal, light should stay on constantly.
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