CT100
Fast, Precise Automotive Circuit Testing
Only £45+ VAT
Professional Load Testing
High-Accuracy Voltage Measurement
Intelligent Polarity Identification
Audible and Visual Safety Alerts
Interchangeable Probe Connections
Extra-Long Cable for Flexible Testing
The TOPDON CT100 Automotive Circuit Tester is designed for fast, reliable electrical diagnostics. Featuring a clear digital voltage display, built-in load testing capability, and audible and visual alerts, it helps technicians and DIY users quickly verify circuit integrity, identify power issues, and locate faults with confidence. Compact, accurate, and easy to use, the CT100 supports a wide range of automotive electrical testing tasks—from routine maintenance to troubleshooting and accessory installation.
Measurement Accuracy
3.3–60V: ±0.1V
60–65V: ±0.2V
Voltage Measurement Range
DC 3.3–65V
Professional Load Testing
Built-in load bulb helps verify circuit integrity and quickly identify weak connections, voltage drops, and wiring faults during troubleshooting.
High-Accuracy Voltage Measurement
Provides ±0.1V accuracy from 3.3–60V and ±0.2V from 60–65V with a real-time digital display for clear, reliable voltage readings during diagnostics.
Intelligent Polarity Identification
Dual-color backlighting clearly indicates positive and negative polarity, with on-screen ± indicators that help prevent reverse connections and support safe, confident testing.
Audible and Visual Safety Alerts
Audible and visual alerts provide immediate feedback for conditions such as high voltage, overheating, and reverse polarity. A power-on tone also helps confirm circuit continuity without constant screen monitoring.
Interchangeable Probe Connections
Standard 4mm banana jacks allow quick switching between clips and probes for different testing needs. The heavy-duty alligator clip is built for durability and consistent performance during repeated use
Extra-Long Cable for Flexible Testing
The 12.5-foot cable provides greater reach when working around vehicles, while the tester's compact design is convenient for both shop and mobile diagnostic environments.
What’s In The Box
CT100 Tester
Adapter
2mm Probe
Carrying Bag
Alligator Clip
Quick User Guide
UK-Based Support & Genuine Warranty Protection
When you buy from TOPDON UK, you’re choosing the confidence of a genuine UK distributor. Every product comes with full UK warranty coverage and fast, reliable local support — no overseas delays, no grey imports, no uncertainty. Just authentic TOPDON tools backed by a dedicated UK team that’s here to help whenever you need it.