{"product_id":"konnwei-kw371-battery-relay-tester-6v-12v-24v-portable-analyzer-with-relay-check-and-cranking-charging-tests","title":"KONNWEI KW371 Battery \u0026 Relay Tester — 6V\/12V\/24V Portable Analyzer with Relay Check and Cranking\/Charging Tests","description":"\u003cp\u003e\u003cstrong\u003eThe KONNWEI KW371 is a portable 2-in-1 diagnostic tool that tests 6V\/12V\/24V batteries and 4\/5-pin relays to quickly identify battery health, cranking issues, charging problems, and relay faults.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThe KW371 combines a full-featured battery analyzer with a relay tester in one handheld instrument, built for workshops, fleet maintenance, and serious DIYers. It supports a broad range of battery chemistries and global rating standards while offering cranking and charging evaluations plus a dedicated relay check for 4- and 5-pin automotive relays. Rugged alligator clips supply power directly from the tested battery and the unit can export reports to a Windows PC.\u003c\/p\u003e\n\n\u003ch3\u003eHow does the KW371 determine battery condition?\u003c\/h3\u003e\n\u003cp\u003eThe tester runs a multi-parameter analysis to give a clear state-of-health result. It measures voltage, internal resistance, state-of-charge (SOC), and estimates state-of-health (SOH), then compares those values to the battery’s rated capacity and selected standard.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eMeasures 10–2000 CCA and 5–220 Ah ranges for accurate sizing.\u003c\/li\u003e\n  \u003cli\u003eWorks with Lead-Acid, AGM flat\/spiral, Gel, EFB, and Lithium types.\u003c\/li\u003e\n  \u003cli\u003eSupports standards: CCA, JIS, EN, DIN, SAE, IEC, GB for worldwide use.\u003c\/li\u003e\n  \u003cli\u003eDelivers simple outcomes: Good Battery, Replace, Bad Cell, or Charge Retest.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat information does it give during cranking and charging tests?\u003c\/h3\u003e\n\u003cp\u003eThe KW371 captures dynamic data during engine start and alternator operation to isolate starting or charging faults. Cranking tests record minimum and maximum voltages and duration in milliseconds, while charging tests evaluate loaded and unloaded ripple to detect alternator or regulator issues.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eCranking: reports starting voltage and cranking time to spot weak starters or depleted batteries.\u003c\/li\u003e\n  \u003cli\u003eCharging: shows voltage under load and ripple readings to reveal alternator problems.\u003c\/li\u003e\n  \u003cli\u003eGraphical waveform display shows real-time voltage behavior for clear interpretation.\u003c\/li\u003e\n  \u003cli\u003eInstant verdicts help decide if the fault is battery, alternator, or starter related.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow does the relay tester function and why is it useful?\u003c\/h3\u003e\n\u003cp\u003eThe integrated relay tester checks 4-pin and 5-pin automotive relays without removing them from the vehicle’s fuse box in most cases. It verifies coil continuity and contact switching, making it easier to pinpoint relay-driven circuit faults such as lighting, fuel pump, or fan failures.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eDiagnoses coil failure and contact wear for 4-pin and 5-pin relays quickly.\u003c\/li\u003e\n  \u003cli\u003eEliminates guesswork—no need to dismantle fuse boxes on many vehicles.\u003c\/li\u003e\n  \u003cli\u003eSaves time during troubleshooting by confirming relay functionality on the spot.\u003c\/li\u003e\n  \u003cli\u003eUseful for both professional shops and advanced DIY electrical checks.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat safety and usability features should I expect?\u003c\/h3\u003e\n\u003cp\u003eThe KW371 is built to be used on-the-go with durable clamps and polarity reverse protection to prevent user errors. It offers an 18-language interface and USB connectivity for software updates and printing diagnostic reports from a Windows PC.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003ePowered directly by the tested battery—no separate batteries required.\u003c\/li\u003e\n  \u003cli\u003ePolarity reverse protection prevents damage from incorrect clip connections.\u003c\/li\u003e\n  \u003cli\u003eGraphical display and clear pass\/fail messages reduce interpretation mistakes.\u003c\/li\u003e\n  \u003cli\u003eUSB PC link enables firmware updates and report export for record-keeping.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: The KONNWEI KW371 suits automotive technicians, fleet managers, RV and boat owners, and experienced DIY mechanics who need a single, portable instrument to diagnose batteries, charging systems, starters, and relays across 6V, 12V, and 24V vehicles. If you service multiple vehicle types or require quick, reliable on-site reports, the KW371 consolidates several diagnostic tasks into one tool.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Can the KW371 test 24V truck batteries?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes — it supports 6V, 12V, and 24V systems and evaluates batteries up to 2000 CCA.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Does the unit require internal batteries to operate?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: No — the KW371 is powered directly from the vehicle battery via the supplied alligator clips.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"KONNWEI","offers":[{"title":"Default Title","offer_id":55172663837015,"sku":"B0GWQN5NS2","price":90.9,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1050\/1524\/7191\/files\/konnwei-kw371-front-panel-display.jpg?v=1790454242","url":"https:\/\/britishgarage.co.uk\/products\/konnwei-kw371-battery-relay-tester-6v-12v-24v-portable-analyzer-with-relay-check-and-cranking-charging-tests","provider":"British Garage","version":"1.0","type":"link"}