{"product_id":"topdon-ct100-circuit-tester","title":"Topdon CT100 Circuit Tester","description":"\u003cp\u003eThe \u003cstrong\u003eTopdon CT100\u003c\/strong\u003e is a battery-free automotive circuit tester built for technicians diagnosing electrical faults across cars, trucks, motorcycles and RVs. With a wide DC voltage range, integrated load testing and instant polarity protection, it delivers fast, dependable fault-finding on the workshop floor — without needing a separate power source.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eWide DC voltage measurement from \u003cstrong\u003e3.3V to 65V\u003c\/strong\u003e with 0.1V resolution and high accuracy (±0.1V across 3.3–60V, ±0.2V from 60–65V)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBuilt-in load test function\u003c\/strong\u003e (5–30V, 1.2A max) — hold the button for 5 seconds to check battery and circuit load capacity\u003c\/li\u003e\n\u003cli\u003eClear \u003cstrong\u003ebacklit LCD\u003c\/strong\u003e with dual-colour polarity protection: red for positive, green for negative, plus on-screen ± indicators to prevent reverse connections\u003c\/li\u003e\n\u003cli\u003eSmart on-screen alerts for \u003cstrong\u003eovervoltage (“H”), overheating (“Hot”) and lamp abnormality (“ER1”)\u003c\/strong\u003e to protect sensitive vehicle electronics\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBattery-free operation\u003c\/strong\u003e with a 12.5ft extra-long test cable and universal 4mm banana-plug connectors for interchangeable probes and clips\u003c\/li\u003e\n\u003cli\u003eSupplied with CT100 tester, 2mm probe, alligator clip, adapter, carrying bag and quick user guide\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eWhat Is the CT100 Used For?\u003c\/h2\u003e\u003cp\u003eThe CT100 is designed for fast, practical electrical fault diagnosis in the workshop or on the road. Common applications include:\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eChecking for voltage presence at fuses, relays, sensors and actuators\u003c\/li\u003e\n\u003cli\u003eVerifying earth continuity and identifying open circuits\u003c\/li\u003e\n\u003cli\u003eLoad testing batteries, charging circuits and auxiliary power supplies\u003c\/li\u003e\n\u003cli\u003eDiagnosing blown fuses, failed bulbs and wiring faults across 12V and 24V systems\u003c\/li\u003e\n\u003cli\u003eSuitable for cars, vans, trucks, motorcycles and RVs\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\u003ctable\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eDetail\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eVoltage range\u003c\/td\u003e\n\u003ctd\u003e3.3V – 65V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eResolution\u003c\/td\u003e\n\u003ctd\u003e0.1V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAccuracy\u003c\/td\u003e\n\u003ctd\u003e±0.1V (3.3–60V) | ±0.2V (60–65V)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLoad test range\u003c\/td\u003e\n\u003ctd\u003e5–30V, max 1.2A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCable length\u003c\/td\u003e\n\u003ctd\u003e12.5ft (approx. 3.8m)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConnectors\u003c\/td\u003e\n\u003ctd\u003eUniversal 4mm banana-plug\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower source\u003c\/td\u003e\n\u003ctd\u003eBattery-free (powered by vehicle circuit)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDisplay\u003c\/td\u003e\n\u003ctd\u003eBacklit LCD with dual-colour polarity indication\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eIn the box\u003c\/td\u003e\n\u003ctd\u003eCT100 tester, 2mm probe, alligator clip, adapter, carrying bag, user guide\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\u003ch2\u003eUK-Based Support \u0026amp; Genuine Warranty Protection\u003c\/h2\u003e\u003cp\u003eWhen you buy from Dunns Automotive, you’re choosing the confidence of a genuine UK distributor. Every product comes with full UK warranty coverage and fast, reliable support from Topdon UK — no overseas delays, no grey imports, no uncertainty. Just authentic TOPDON UK tools backed by a dedicated UK team that’s here to help whenever you need it.\u003c\/p\u003e","brand":"Topdon","offers":[{"title":"Default Title","offer_id":53812821950792,"sku":"424","price":45.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0980\/4437\/9464\/files\/424.jpg?v=1786949713","url":"https:\/\/adasequipment.co.uk\/products\/topdon-ct100-circuit-tester","provider":"Dunns Automotive | ADAS Equipment","version":"1.0","type":"link"}