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Red circuit tester with 7 inch stainless probe and coiled 24 foot cord

OTC 3642 Truck Circuit Tester 12V–24V 24 ft Cord Red

SKU CH-1XP6-VMVNN

Tests 12V–24V truck circuits with a 24‑foot coiled cord and stainless‑steel probe

  • Features12V–24V Truck Circuit Tester, Battery Powered, false
  • Height13.9 L x 2.1 W x 0.1 H inches
  • Width13.9 L x 2.1 W x 0.1 H inches
  • Length13.9 L x 2.1 W x 0.1 H inches
  • Weight0.75 pounds
  • Sports Team1 Piece
  • Tests 12V–24V truck circuits with 7-inch stainless probe
  • Locates shorts, grounds and open circuits in heavy-duty systems
  • Red coiled cord stretches to 24 feet for extended reach
  • Extra-large clamp grips bigger nuts, bolts and grounds
  • Lightweight 0.75 lb design with 13.9 x 2.1 x 0.1 in profile

Truck Circuit Tester 12V–24V

The OTC 3642 is a battery-powered circuit tester built for 12V–24V truck electrical systems. It helps technicians locate shorts, grounds and open circuits quickly. The stainless steel probe measures 7 inches for deep access. The tool weighs .75 pounds and is designed for heavy-duty use.

Voltage Range 12V–24V

This tester operates on 12V–24V systems only, so it matches most light- and medium-duty truck platforms. It will not work on 6V or higher-voltage commercial systems. Verify the vehicle voltage before purchase to ensure compatibility.

24 Foot Coiled Cord and Large Clamp

The red coiled cord stretches to 24 feet, giving reach across large engine bays without excess slack. An extra-large clamp attaches to bigger nuts, bolts and ground points that smaller clamps cannot grip. Both features reduce setup time on heavy-duty trucks.

Highlights

  • Tests 12V–24V truck circuits with 7-inch stainless probe
  • Locates shorts, grounds and open circuits in heavy-duty systems
  • Red coiled cord stretches to 24 feet for extended reach
  • Extra-large clamp grips bigger nuts, bolts and grounds
  • Lightweight 0.75 lb design with 13.9 x 2.1 x 0.1 in profile

Specifications

BrandOTC
Features12V–24V Truck Circuit Tester, Battery Powered, false
Height13.9 L x 2.1 W x 0.1 H inches
Width13.9 L x 2.1 W x 0.1 H inches
Length13.9 L x 2.1 W x 0.1 H inches
Weight0.75 pounds
Sports Team1 Piece
TypeVoltmeter

Questions about this item

What does the 12V–24V range mean when I am testing a heavy-duty truck circuit?

The tester works on both 12-volt and 24-volt electrical systems, so you can diagnose lighting, starter and accessory circuits on light trucks and Class 7-8 vehicles without switching tools.

How does the coiled cord behave when I need the full 24 foot reach?

The red coiled cord stays compact during storage and stretches to a full 24 feet when extended, giving you room to move around the cab and chassis while the clamp remains secured.

What clearance does the 7 inch stainless probe and extra-large clamp need to fit on a battery post or frame bolt?

The 7 inch probe reaches into tight harnesses, and the oversized clamp opens wide enough to grip large nuts, bolts and frame grounds that smaller clamps cannot.

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