{"id":3605,"date":"2026-09-29T05:43:52","date_gmt":"2026-09-29T05:43:52","guid":{"rendered":"https:\/\/shop.autoboss.com\/?post_type=product&#038;p=3605"},"modified":"2026-10-09T08:20:31","modified_gmt":"2026-10-09T08:20:31","slug":"autool-dm303-automotive-multimeter","status":"publish","type":"product","link":"https:\/\/autoboss.com\/es\/product\/autool-dm303-automotive-multimeter\/","title":{"rendered":"AUTOOL DM303 True RMS Automotive Multimeter with Oscilloscope &#038; Signal Output"},"content":{"rendered":"<div class=\"abd-pd\" data-abd-version=\"1\">\n<header class=\"abd-hero\">\n<h3>Meter, Scope and Automotive Circuit Tests in One Handheld<\/h3>\n<p class=\"abd-lead\">The DM303 combines a True RMS auto-ranging multimeter and oscilloscope with dedicated cranking, ignition, injector, relay, signal-output and K\/CAN line modes for car, truck, bus and EV circuit work. Batteries are not included.<\/p>\n<ul class=\"abd-facts\">\n<li>DMM + Oscilloscope<\/li>\n<li>12 Test Functions<\/li>\n<li>5 A Drive Current<\/li>\n<li>6 Test Lead Types<\/li>\n<li>2.8-inch Color Screen<\/li>\n<\/ul>\n<\/header>\n<section class=\"abd-sec\" id=\"abd-features\">\n<h4>Key Features<\/h4>\n<ol class=\"abd-features\">\n<li>\n<h5>True RMS Auto-Ranging Meter<\/h5>\n<p>DC\/AC voltage, current, resistance, diode and frequency, with auto range to cut manual range selection.<\/p>\n<\/li>\n<li>\n<h5>Cranking and Ignition Checks<\/h5>\n<p>Records minimum battery voltage during starting and views ignition pulse signals.<\/p>\n<\/li>\n<li>\n<h5>Injector and Relay Testing<\/h5>\n<p>Drives supported electromagnetic injectors, including supported GDI injectors, and reads real-time injector signals; also tests relays.<\/p>\n<\/li>\n<li>\n<h5>Signal Output<\/h5>\n<p>5 V square, 5 Vpp sine and 12 V square outputs for signal simulation on a documented, permitted load.<\/p>\n<\/li>\n<li>\n<h5>K\/CAN and K\/LIN Line Data<\/h5>\n<p>Views bus line data for circuit-level diagnosis.<\/p>\n<\/li>\n<li>\n<h5>Kit in a Toolbox<\/h5>\n<p>Rear stand for upright viewing, built-in flashlight, and a toolbox that holds the meter and leads together.<\/p>\n<\/li>\n<\/ol>\n<\/section>\n<section class=\"abd-sec\" id=\"abd-specs\">\n<h4>More Specifications<\/h4>\n<div class=\"abd-table-wrap\">\n<table class=\"abd-table abd-specs\">\n<tbody>\n<tr>\n<th scope=\"row\">Injector drive signal<\/th>\n<td>500\u20136000 rpm<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\">Data hold<\/th>\n<td>Data lock and clear<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\">Interface languages<\/th>\n<td>Including English, French, Portuguese, Polish, Spanish, Japanese, Russian, Italian, German, Dutch, Korean and Chinese<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\">Optional lithium battery<\/th>\n<td>503450 3.7 V 1000 mAh style shown in the reference image; confirm connector and size before fitting<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/section>\n<section class=\"abd-sec\" id=\"abd-compare\">\n<h4>DM303 vs DM301<\/h4>\n<div class=\"abd-table-wrap\">\n<table class=\"abd-table abd-compare\">\n<thead>\n<tr>\n<th scope=\"col\"><\/th>\n<th scope=\"col\" class=\"is-current\">DM303<\/th>\n<th scope=\"col\">DM301<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<th scope=\"row\">Funciones<\/th>\n<td class=\"is-current\">12<\/td>\n<td>6<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\">Test lead types<\/th>\n<td class=\"is-current\">6<\/td>\n<td>2<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\">Circuit drive current<\/th>\n<td class=\"is-current\">5 A output \/ 5 A input<\/td>\n<td>No<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\">Injector drive signal<\/th>\n<td class=\"is-current\">500\u20136000 rpm<\/td>\n<td>No<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\">Added test modes<\/th>\n<td class=\"is-current\">Injector, relay, circuit, cranking, signal simulation, CAN and K\/LIN line data<\/td>\n<td>Voltage, current, resistance, frequency, oscilloscope, ignition pulse only<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/section>\n<section class=\"abd-sec\" id=\"abd-box\">\n<h4>What&#8217;s in the Box<\/h4>\n<ul class=\"abd-box\">\n<li>DM303 automotive diagnostic multimeter<\/li>\n<li>Portable toolbox<\/li>\n<li>Multifunction test lead<\/li>\n<li>Battery clip cable<\/li>\n<li>Multimeter probes<\/li>\n<li>Jumper and adapter cables<\/li>\n<li>Additional test leads<\/li>\n<li>User manual<\/li>\n<\/ul>\n<figure class=\"abd-fig\"><img decoding=\"async\" src=\"https:\/\/autoboss.com\/wp-content\/uploads\/autool-catalog\/media\/4d5f38e54fde7ccff17b83b3.webp\" alt=\"AUTOOL DM303 multimeter with toolbox, user manual and test leads\" width=\"1200\" height=\"1200\" loading=\"lazy\"><figcaption>Main unit, toolbox and the supplied test leads. Batteries are not included.<\/figcaption><\/figure>\n<\/section>\n<section class=\"abd-sec\" id=\"abd-use\">\n<h4>How to Use<\/h4>\n<ol class=\"abd-steps\">\n<li><b>Define the measurement<\/b><span>Use the wiring diagram to identify the expected signal, reference point and safe mode.<\/span><\/li>\n<li><b>Inspect leads and ratings<\/b><span>Confirm the terminal, fuse, lead and probe ratings for the task.<\/span><\/li>\n<li><b>Select the mode<\/b><span>Choose the function and start on a safe range.<\/span><\/li>\n<li><b>Qualify any active output<\/b><span>Before injector, relay or signal output, confirm component type, pinout, supply, current and permitted mode.<\/span><\/li>\n<li><b>Probe the circuit<\/b><span>Connect to the correct reference and test point without bridging terminals.<\/span><\/li>\n<li><b>Record and verify<\/b><span>Note the value, compare it with the vehicle specification and recheck before naming a root cause.<\/span><\/li>\n<\/ol>\n<p class=\"abd-note\">Modes, ranges and safety: <a href=\"https:\/\/autoboss.com\/wp-content\/uploads\/autool-catalog\/media\/c58024d6939dad6d5b4dcafb.pdf\" target=\"_blank\" rel=\"noopener\">DM303 user manual (PDF)<\/a>.<\/p>\n<\/section>\n<section class=\"abd-sec\" id=\"abd-notes\">\n<h4>Good to Know<\/h4>\n<div class=\"abd-notes\">\n<div class=\"abd-note-group is-caution\">\n<h5><span class=\"abd-tag\">Caution<\/span><\/h5>\n<ul>\n<li>Batteries are not included. Use 4 \u00d7 1.5 V dry batteries or a compatible lithium battery, purchased separately.<\/li>\n<li>Never charge dry batteries in the device; only a compatible rechargeable lithium battery may be charged.<\/li>\n<li>Keep injector drive and signal outputs off ECU outputs, SRS circuits, powered data lines and unknown modules.<\/li>\n<li>120 V injectors are not supported.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/section>\n<section class=\"abd-sec\" id=\"abd-faq\">\n<h4>FAQ<\/h4>\n<details class=\"abd-faq\" name=\"abd-faq\">\n<summary>What does the cranking test result mean?<\/summary>\n<p>The DM303 records minimum battery voltage during starting and uses 9.6 V as a general reference. A lower reading can point to a weak or aging battery or a starting-system issue; apply the battery or vehicle maker&#8217;s procedure.<\/p>\n<\/details>\n<details class=\"abd-faq\" name=\"abd-faq\">\n<summary>Can it replace a full vehicle diagnostic scanner?<\/summary>\n<p>No. K\/CAN line data helps with circuit-level diagnosis, but it is not a full vehicle scan.<\/p>\n<\/details>\n<details class=\"abd-faq\" name=\"abd-faq\">\n<summary>Does a drive response prove an injector is good?<\/summary>\n<p>No. It does not by itself prove spray pattern, flow or root cause.<\/p>\n<\/details>\n<\/section>\n<\/div>","protected":false},"excerpt":{"rendered":"<ul>\n<li><strong>True RMS DMM + Oscilloscope:<\/strong> Combine True RMS auto-ranging electrical measurements with oscilloscope waveform observation.<\/li>\n<li><strong>Cranking, Ignition + Vehicle Signals:<\/strong> Check cranking behavior, ignition pulses, and dedicated vehicle signals from one handheld unit.<\/li>\n<li><strong>Injector + Relay Testing:<\/strong> Use the supported drive and observation modes for electromagnetic injectors, excluding 120 V injectors, plus compatible relays.<\/li>\n<li><strong>5 V \/ 12 V Signals + K\/CAN View:<\/strong> Generate 5 V square, 5 Vpp sine, or 12 V square signals and observe K\/CAN line data in the dedicated modes.<\/li>\n<li><strong>2.8-Inch Multi-Language Screen:<\/strong> Read menus on the brightness-adjustable color screen and carry the tester with its leads in the toolbox.<\/li>\n<\/ul>","protected":false},"featured_media":12446,"comment_status":"open","ping_status":"closed","template":"","meta":{"_gspb_post_css":""},"product_brand":[128],"product_cat":[62,249],"product_tag":[160,161],"class_list":["post-3605","product","type-product","status-publish","has-post-thumbnail","product_brand-autool","product_cat-best-selling-products","product_cat-multimeters-oscilloscopes","product_tag-digital-multimeter","product_tag-multimeter","first","instock","shipping-taxable","purchasable","product-type-variable"],"_links":{"self":[{"href":"https:\/\/autoboss.com\/es\/wp-json\/wp\/v2\/product\/3605","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/autoboss.com\/es\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/autoboss.com\/es\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/autoboss.com\/es\/wp-json\/wp\/v2\/comments?post=3605"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/autoboss.com\/es\/wp-json\/wp\/v2\/media\/12446"}],"wp:attachment":[{"href":"https:\/\/autoboss.com\/es\/wp-json\/wp\/v2\/media?parent=3605"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/autoboss.com\/es\/wp-json\/wp\/v2\/product_brand?post=3605"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/autoboss.com\/es\/wp-json\/wp\/v2\/product_cat?post=3605"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/autoboss.com\/es\/wp-json\/wp\/v2\/product_tag?post=3605"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}