CT100 Professional Automotive Circuit Tester – Digital Voltage Tester with Load Test, Polarity Protection & 12.5ft Cable

The CT100 is a professional automotive circuit tester designed for technicians and serious DIY users who need fast, accurate, and reliable electrical diagnostics. Built for daily use, it combines precision voltage testing, professional load testing, instant polarity detection, and rugged durability into one practical tool. With battery-free operation, audible and visual alerts, and broad vehicle compatibility, the CT100 helps eliminate guesswork and speeds up electrical troubleshooting.

Key Features
✅ Professional Load Testing for Faster Electrical Diagnosis
Unlike standard test lights, the CT100 includes an advanced load test function (DC 5–30V, 1.2A Max) to help technicians quickly evaluate battery and circuit performance.
Benefits include:
✔ Detect weak batteries
✔ Identify voltage drops
✔ Spot poor connections
✔ Diagnose aging electrical systems
✔ Improve troubleshooting accuracy
Simply hold the button for 5 seconds to perform load testing.

✅ Precision Digital Voltage Testing
The CT100 features a backlit digital display for clear, accurate readings in any environment.
Testing Range:
✔ DC 3.3V–65V
✔ 0.1V resolution
✔ ±0.1V accuracy (3.3–60V)
✔ ±0.2V accuracy (60–65V)
This expanded range makes it ideal for modern vehicle systems beyond standard 12V testing.

✅ Instant Polarity Detection & Anti-Reverse Protection
Dual-color visual indicators provide immediate polarity feedback:
✔ Red: Positive
✔ Green: Negative
On-screen ± indicators help prevent reverse connections and reduce the risk of damaging sensitive electronics.

✅ Battery-Free, Safe Operation
No batteries required means less maintenance, no downtime, and safer daily use.
Integrated protections include:
✔ Overvoltage alerts
✔ Overheating warnings
✔ Component status monitoring

✅ Intuitive Status Light Indicators
Clear system alerts keep you informed during every test.
Indicator Alerts:
✔ Positive / Negative polarity
✔ “H” = Overvoltage
✔ “Hot” = Overheating
✔ “ER1” = Lamp abnormality

✅ Extra-Long 12.5-Foot Cable for Better Reach
Designed for real-world shop use, the extended oil-resistant cable allows easy access to difficult areas without repositioning.
Features:
✔ 12.5 ft test lead
✔ Oil-resistant construction
✔ Universal 4mm banana jack
✔ Interchangeable probes and clips

✅ Wide Vehicle Compatibility
With a 3.3–65V operating range, the CT100 supports multiple vehicle platforms, including:
✔ 12V systems
✔ 24V systems
✔ 36V systems

✅ Ideal for:
Cars
Trucks
RVs
Commercial vehicles
EV diagnostics

✅ Common Applications
The CT100 is perfect for:
✔ Fuse testing
✔ Circuit integrity checks
✔ Voltage verification
✔ Wiring fault tracing
✔ Connector diagnostics
✔ Starting system troubleshooting
✔ Battery and charging system analysis

✅ Built for Professionals & DIYers
The CT100 combines rugged construction, precise electronics, and intuitive operation, making it equally effective for professional technicians and hands-on vehicle owners.

✅ What’s in the Box
CT100 Circuit Tester
2mm Probe
Alligator Clip
Adapter
Carrying Bag
Quick User Guide

✅ Why Choose the CT100?
The CT100 goes beyond a standard test light by combining advanced voltage diagnostics, professional load testing, instant polarity feedback, and extended reach in one dependable tool. Whether you’re diagnosing a complex electrical fault or performing quick system checks, it delivers professional performance without unnecessary complexity.

✅ Ideal For
Automotive technicians
Electrical diagnostics
DIY vehicle repair
Fleet maintenance
RV service
Commercial vehicle troubleshooting

✅ Key Advantages
Professional Load Test Function
3.3–65V Wide Voltage Range
Precision Digital Display
Dual-Color Polarity Protection
Battery-Free Operation
Overvoltage & Overheat Alerts
12.5ft Oil-Resistant Cable
Multi-Vehicle Compatibility