{"id":527200,"date":"2026-07-16T20:31:15","date_gmt":"2026-07-17T00:31:15","guid":{"rendered":"https:\/\/www.fs1inc.com\/blog\/?p=527200"},"modified":"2026-07-16T20:31:15","modified_gmt":"2026-07-17T00:31:15","slug":"1999-lexus-rx300-pcm-replacement-guide","status":"publish","type":"post","link":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/","title":{"rendered":"1999 Lexus RX300 PCM and ECM Relearn Procedures"},"content":{"rendered":"<div class=\"container\">\n<section class=\"hero\">\n<div class=\"code-badge\">PCM<\/div>\n<h1>1999 Lexus RX300 PCM and ECM Relearn Procedures<\/h1>\n<p class=\"hero-subtitle\">In the 1999 Lexus RX300 the Powertrain Control Module and Engine Control Module manage fuel delivery, ignition timing, and transmission shift logic. A failure in either unit can disrupt engine speed regulation, cause stalling, or trigger communication errors with diagnostic tools, leading to drivability problems.<\/p>\n<\/section>\n<div class=\"quick-summary\">\n<h2>Quick Summary<\/h2>\n<ul>\n<li>Powertrain Control Module relearn takes about half an hour of labor.<\/li>\n<li>Engine Control Module replacement also requires roughly half an hour.<\/li>\n<li>Both modules are accessed from the instrument panel according to the factory wiring guide.<\/li>\n<li>Flagship One units arrive pre\u2011programmed, eliminating post\u2011install coding steps.<\/li>\n<\/ul>\n<\/div>\n<div class=\"info-section\">\n<p>When a 1999 Lexus RX300 exhibits symptoms like rough idle, unexpected stalling, or loss of power, the vehicle\u2019s control computers may need to be reset or replaced. Understanding the relearn process for the Powertrain Control Module (PCM) and Engine Control Module (ECM) helps you ensure the engine runs smoothly after service. This guide explains where the modules live, what labor is involved, and how Flagship One\u2019s pre\u2011programmed units simplify the job.<\/p>\n<\/div>\n<div class=\"info-section\">\n<h2>What the PCM Does in a 1999 Lexus RX300<\/h2>\n<p>The PCM and ECM in a 1999 Lexus RX300 serve as the brain for engine and transmission functions, continuously adjusting fuel, spark, and shift timing based on sensor input. Their proper operation is essential for smooth acceleration, fuel efficiency, and emission compliance. When a replacement is performed, the new unit must be aligned with the vehicle\u2019s existing calibrations, which is why a relearn procedure is required. The process ensures the module recognizes sensor ranges and adapts to the vehicle\u2019s specific characteristics. For a proper swap, technicians often use <a href=\"https:\/\/www.fs1inc.com\/toyota-ecm-pcm-ecu-engine-computer\/lexus-ecm-pcm-ecu-engine-computer\/rx300-engine-computers.html\">replacement engine control modules for the RX300<\/a> to match factory specifications.<\/p>\n<\/div>\n<div class=\"info-section\">\n<h2>Where the PCM Is Located and What Replacement Involves<\/h2>\n<p>The factory wiring guide places the engine control unit within the instrument panel, making it reachable from the dash area. Removing the module typically involves disconnecting the connector, extracting mounting bolts, and taking the unit out of its housing. Installation reverses those steps, securing the new module with the same fasteners. The labor guide lists 0.6 hours for an Engine Control Module replacement and 0.5 hours for a Powertrain Control Module relearn, reflecting the relatively straightforward access once the panel is opened.<\/p>\n<figure style=\"margin:22px auto;text-align:center;max-width:720px\"><img decoding=\"async\" style=\"max-width:100%;height:auto;border:1px solid #e2e6ec;border-radius:8px\" src=\"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2026\/07\/1999-lexus-rx300-ecu-location-card.webp\" alt=\"1999 Lexus RX300 PCM location diagram\" loading=\"lazy\"\/><figcaption style=\"font-size:13px;color:#667085;margin-top:8px\">Typical PCM mounting area on the 1999 Lexus RX300 (reference).<\/figcaption><\/figure>\n<table style=\"width:100%;border-collapse:collapse;margin:18px 0;font-size:15px\">\n<tr>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">Operation<\/th>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">Configuration<\/th>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">Book Time<\/th>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Powertrain Control Module Relearn<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">All configurations<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">0.5 hr<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Powertrain Control Module R&amp;R<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">All configurations<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">0.6 hr<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Engine Control Module R&amp;R<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">All configurations<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">0.6 hr<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Engine Control Module Relearn<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">All configurations<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">0.5 hr<\/td>\n<\/tr>\n<\/table>\n<\/div>\n<div class=\"info-section\">\n<h2>Programming Requirements After Replacement<\/h2>\n<p>After installing a new PCM or ECM, the factory procedure calls for a relearn sequence to synchronize the module with the vehicle\u2019s sensors and transmission controller. Flagship One supplies units that arrive VIN\u2011programmed, so the required relearn steps are already completed at the factory. This means the technician can focus on physical installation and final verification without performing additional coding, as the <a href=\"https:\/\/www.fs1inc.com\/1999-lexus-rx300-3-0l-pcm-engine-computer-ecm-ecu-programmed-plug-play.html\">a VIN-programmed replacement unit<\/a> includes the correct calibration data.<\/p>\n<\/div>\n<div class=\"info-section\">\n<h2>Symptoms of a Failing PCM<\/h2>\n<p>Typical signs of a failing PCM or ECM in a 1999 Lexus RX300 include a no\u2011start condition, intermittent stalling, unexpected loss of power, and diagnostic trouble codes that prevent communication with a scan tool. You may also notice rough idle or erratic shifting when the control module cannot process sensor data correctly. One common fault that appears is timing signal error, which indicates the module is not receiving a proper timing reference and can lead to engine shutdown.<\/p>\n<\/div>\n<div class=\"info-section\">\n<h2>Factory Service Bulletins Worth Knowing<\/h2>\n<p>Service bulletin TC002\u201103 addresses ECM reset memory functions for model years 1998\u20112005, offering revised procedures for clearing stored data after replacement. This bulletin outlines the steps to ensure the ECM returns to a known baseline state.<\/p>\n<table style=\"width:100%;border-collapse:collapse;margin:18px 0;font-size:15px\">\n<tr>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">Bulletin<\/th>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">Subject<\/th>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">What It Addresses<\/th>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><b>TC002-03<\/b><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">:TC002-03: ECM Reset Memory Function: 98-05 Applicable Models (Revised)<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">&mdash;<\/td>\n<\/tr>\n<\/table>\n<\/div>\n<div class=\"info-section\">\n<h2>Protecting the PCM in Your 1999 Lexus RX300<\/h2>\n<ul style=\"margin:14px 0 6px 0;padding-left:26px\">\n<li style=\"margin:10px 0;line-height:1.65\">Maintain a healthy charging system to avoid voltage fluctuations.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\">Inspect and clean all ground connections and connector pins regularly.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\">Use surge protectors or avoid high\u2011voltage jump starts that can stress the modules.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\">Promptly address any stored diagnostic codes before they recur.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\">Keep connector seals intact to protect against moisture intrusion.<\/li>\n<\/ul>\n<\/div>\n<div class=\"info-section\">\n<h2>Frequently Asked Questions<\/h2>\n<h3>What is the typical labor time to replace the PCM in a 1999 Lexus RX300?<\/h3>\n<p>The factory book time for a Powertrain Control Module replacement on this model is listed as 0.5 hours, reflecting the relatively simple access from the instrument panel.<\/p>\n<h3>Do I need special tools to perform the ECM relearn on a 1999 Lexus RX300?<\/h3>\n<p>The relearn procedure follows the factory guidelines and does not require proprietary tools; a standard scan tool can initiate the process if the module is not pre\u2011programmed.<\/p>\n<h3>Can a VIN\u2011programmed Flagship One unit eliminate the need for an ECM reset on a 1999 Lexus RX300?<\/h3>\n<p>Yes, Flagship One\u2019s units arrive with the correct VIN data already loaded, so the post\u2011install reset steps outlined in bulletin TC002\u201103 are already satisfied.<\/p>\n<\/div>\n<div class=\"info-section\">\n<p>When the PCM or ECM in your 1999 Lexus RX300 requires service, you can choose a brand\u2011new factory\u2011spec unit or a refurbished replacement that meets the same performance standards. Both options restore engine control, but a Flagship One refurbished module arrives pre\u2011programmed, reducing shop time and eliminating the need for additional coding steps. Evaluate your repair schedule and decide which path aligns best with your workload and budget.<\/p>\n<figure style=\"margin:22px auto;text-align:center;max-width:720px\"><img decoding=\"async\" style=\"max-width:100%;height:auto;border:1px solid #e2e6ec;border-radius:8px\" src=\"https:\/\/www.fs1inc.com\/media\/wysiwyg\/googleshop\/toyotapanic\/toyota-pcm-panic-1.jpg\" alt=\"Refurbished VIN-programmed PCM for the 1999 Lexus RX300\" loading=\"lazy\"\/><figcaption style=\"font-size:13px;color:#667085;margin-top:8px\">A refurbished, VIN-programmed replacement PCM for the 1999 Lexus RX300 from Flagship One.<\/figcaption><\/figure>\n<p>Flagship One stocks a <a href=\"https:\/\/www.fs1inc.com\/1999-lexus-rx300-3-0l-pcm-engine-computer-ecm-ecu-programmed-plug-play.html\"><b>refurbished, VIN-programmed PCM for the 1999 Lexus RX300<\/b><\/a> with a lifetime warranty, free shipping and no core charge. The full <a href=\"https:\/\/www.fs1inc.com\/toyota-ecm-pcm-ecu-engine-computer\/lexus-ecm-pcm-ecu-engine-computer\/rx300-engine-computers.html\">Lexus RX300 module lineup<\/a> covers other engine configurations as well.<\/p>\n<\/div>\n<div class=\"info-section\">\n<h2>Final Thoughts<\/h2>\n<p>Properly addressing PCM or ECM issues in a 1999 Lexus RX300 helps maintain reliable performance and fuel efficiency. Whether you opt for a new or refurbished unit, ensuring the relearn procedure is completed protects your vehicle\u2019s drivability. Contact a qualified technician to assess the best solution for your situation.<\/p>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>If your 1999 Lexus RX300 shows no\u2011start or erratic performance, improper PCM\/ECM relearn can cause issues; proper reset restores engine control.<\/p>\n","protected":false},"author":1,"featured_media":522188,"comment_status":"open","ping_status":"closed","sticky":false,"template":"elementor_header_footer","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[258,298],"tags":[52,110,563],"class_list":["post-527200","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-car","category-lexus","tag-52","tag-lexus-computer","tag-rx300"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.0 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>1999 Lexus RX300 PCM and ECM Relearn Procedures - Flagship One Blog<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"1999 Lexus RX300 PCM and ECM Relearn Procedures - Flagship One Blog\" \/>\n<meta property=\"og:description\" content=\"If your 1999 Lexus RX300 shows no\u2011start or erratic performance, improper PCM\/ECM relearn can cause issues; proper reset restores engine control.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/\" \/>\n<meta property=\"og:site_name\" content=\"Flagship One Blog\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/flagshipone\" \/>\n<meta property=\"article:author\" content=\"https:\/\/www.facebook.com\/flagshipone\/\" \/>\n<meta property=\"article:published_time\" content=\"2026-07-17T00:31:15+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2026\/07\/1999-lexus-rx300-ecu-location-card.webp\" \/>\n\t<meta property=\"og:image:width\" content=\"1200\" \/>\n\t<meta property=\"og:image:height\" content=\"675\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/webp\" \/>\n<meta name=\"author\" content=\"FlagshipOne\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@theflagshipone\" \/>\n<meta name=\"twitter:site\" content=\"@theflagshipone\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"FlagshipOne\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"5 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/1999-lexus-rx300-pcm-replacement-guide\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/1999-lexus-rx300-pcm-replacement-guide\\\/\"},\"author\":{\"name\":\"FlagshipOne\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#\\\/schema\\\/person\\\/a3cf463514bd03eb7656953ef8f75700\"},\"headline\":\"1999 Lexus RX300 PCM and ECM Relearn Procedures\",\"datePublished\":\"2026-07-17T00:31:15+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/1999-lexus-rx300-pcm-replacement-guide\\\/\"},\"wordCount\":993,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/1999-lexus-rx300-pcm-replacement-guide\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/07\\\/1999-lexus-rx300-ecu-location-card.webp\",\"keywords\":[\"1999\",\"Lexus\",\"Rx300\"],\"articleSection\":[\"Car\",\"Lexus\"],\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/1999-lexus-rx300-pcm-replacement-guide\\\/#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/1999-lexus-rx300-pcm-replacement-guide\\\/\",\"url\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/1999-lexus-rx300-pcm-replacement-guide\\\/\",\"name\":\"1999 Lexus RX300 PCM and ECM Relearn Procedures - Flagship One Blog\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/1999-lexus-rx300-pcm-replacement-guide\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/1999-lexus-rx300-pcm-replacement-guide\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/07\\\/1999-lexus-rx300-ecu-location-card.webp\",\"datePublished\":\"2026-07-17T00:31:15+00:00\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/1999-lexus-rx300-pcm-replacement-guide\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/1999-lexus-rx300-pcm-replacement-guide\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/1999-lexus-rx300-pcm-replacement-guide\\\/#primaryimage\",\"url\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/07\\\/1999-lexus-rx300-ecu-location-card.webp\",\"contentUrl\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/07\\\/1999-lexus-rx300-ecu-location-card.webp\",\"width\":1200,\"height\":675,\"caption\":\"Typical ECU mounting area on the 1999 Lexus RX300 \u2014 reference card\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/1999-lexus-rx300-pcm-replacement-guide\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"1999 Lexus RX300 PCM and ECM Relearn Procedures\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#website\",\"url\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/\",\"name\":\"Flagship One Blog\",\"description\":\"Flagship One Inc. OEM Engine Computers  Control Modules\",\"publisher\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#organization\",\"name\":\"Flagship One, Inc.\",\"url\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/wp-content\\\/uploads\\\/2019\\\/06\\\/web-lg-fs1-logo.png\",\"contentUrl\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/wp-content\\\/uploads\\\/2019\\\/06\\\/web-lg-fs1-logo.png\",\"width\":1341,\"height\":1098,\"caption\":\"Flagship One, Inc.\"},\"image\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#\\\/schema\\\/logo\\\/image\\\/\"},\"sameAs\":[\"https:\\\/\\\/www.facebook.com\\\/flagshipone\",\"https:\\\/\\\/x.com\\\/theflagshipone\",\"https:\\\/\\\/www.instagram.com\\\/flagship_one\",\"https:\\\/\\\/www.youtube.com\\\/channel\\\/UC0oyKphffBM2qkJ-gKPmMXw\"]},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#\\\/schema\\\/person\\\/a3cf463514bd03eb7656953ef8f75700\",\"name\":\"FlagshipOne\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/351b81e51993825aea73280c48061a7205fdd2189730ebbdee5d63894c5cebb4?s=96&d=mm&r=g\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/351b81e51993825aea73280c48061a7205fdd2189730ebbdee5d63894c5cebb4?s=96&d=mm&r=g\",\"contentUrl\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/351b81e51993825aea73280c48061a7205fdd2189730ebbdee5d63894c5cebb4?s=96&d=mm&r=g\",\"caption\":\"FlagshipOne\"},\"description\":\"The world's top supplier of programmed OEM (Original Equipment Manufacturer) Powertrain Control Modules (PCM), Engine Control Modules (ECM), Injection Control Modules (IDM), Body Control Modules (BCM), Transmission Control Modules (TCM), Engine Control Units and all other car control units. With over a decade in the business, we are the most reliable source when it comes to programming services for replacement engine control modules.\",\"sameAs\":[\"https:\\\/\\\/www.fs1inc.com\\\/\",\"https:\\\/\\\/www.facebook.com\\\/flagshipone\\\/\",\"https:\\\/\\\/www.instagram.com\\\/flagship_one\\\/\",\"https:\\\/\\\/www.linkedin.com\\\/company\\\/fs1inc\"],\"url\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/author\\\/flagship1inc\\\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"1999 Lexus RX300 PCM and ECM Relearn Procedures - Flagship One Blog","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/","og_locale":"en_US","og_type":"article","og_title":"1999 Lexus RX300 PCM and ECM Relearn Procedures - Flagship One Blog","og_description":"If your 1999 Lexus RX300 shows no\u2011start or erratic performance, improper PCM\/ECM relearn can cause issues; proper reset restores engine control.","og_url":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/","og_site_name":"Flagship One Blog","article_publisher":"https:\/\/www.facebook.com\/flagshipone","article_author":"https:\/\/www.facebook.com\/flagshipone\/","article_published_time":"2026-07-17T00:31:15+00:00","og_image":[{"width":1200,"height":675,"url":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2026\/07\/1999-lexus-rx300-ecu-location-card.webp","type":"image\/webp"}],"author":"FlagshipOne","twitter_card":"summary_large_image","twitter_creator":"@theflagshipone","twitter_site":"@theflagshipone","twitter_misc":{"Written by":"FlagshipOne","Est. reading time":"5 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/#article","isPartOf":{"@id":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/"},"author":{"name":"FlagshipOne","@id":"https:\/\/www.fs1inc.com\/blog\/#\/schema\/person\/a3cf463514bd03eb7656953ef8f75700"},"headline":"1999 Lexus RX300 PCM and ECM Relearn Procedures","datePublished":"2026-07-17T00:31:15+00:00","mainEntityOfPage":{"@id":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/"},"wordCount":993,"commentCount":0,"publisher":{"@id":"https:\/\/www.fs1inc.com\/blog\/#organization"},"image":{"@id":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/#primaryimage"},"thumbnailUrl":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2026\/07\/1999-lexus-rx300-ecu-location-card.webp","keywords":["1999","Lexus","Rx300"],"articleSection":["Car","Lexus"],"inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/#respond"]}]},{"@type":"WebPage","@id":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/","url":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/","name":"1999 Lexus RX300 PCM and ECM Relearn Procedures - Flagship One Blog","isPartOf":{"@id":"https:\/\/www.fs1inc.com\/blog\/#website"},"primaryImageOfPage":{"@id":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/#primaryimage"},"image":{"@id":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/#primaryimage"},"thumbnailUrl":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2026\/07\/1999-lexus-rx300-ecu-location-card.webp","datePublished":"2026-07-17T00:31:15+00:00","breadcrumb":{"@id":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/#primaryimage","url":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2026\/07\/1999-lexus-rx300-ecu-location-card.webp","contentUrl":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2026\/07\/1999-lexus-rx300-ecu-location-card.webp","width":1200,"height":675,"caption":"Typical ECU mounting area on the 1999 Lexus RX300 \u2014 reference card"},{"@type":"BreadcrumbList","@id":"https:\/\/www.fs1inc.com\/blog\/1999-lexus-rx300-pcm-replacement-guide\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.fs1inc.com\/blog\/"},{"@type":"ListItem","position":2,"name":"1999 Lexus RX300 PCM and ECM Relearn Procedures"}]},{"@type":"WebSite","@id":"https:\/\/www.fs1inc.com\/blog\/#website","url":"https:\/\/www.fs1inc.com\/blog\/","name":"Flagship One Blog","description":"Flagship One Inc. OEM Engine Computers  Control Modules","publisher":{"@id":"https:\/\/www.fs1inc.com\/blog\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.fs1inc.com\/blog\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/www.fs1inc.com\/blog\/#organization","name":"Flagship One, Inc.","url":"https:\/\/www.fs1inc.com\/blog\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.fs1inc.com\/blog\/#\/schema\/logo\/image\/","url":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2019\/06\/web-lg-fs1-logo.png","contentUrl":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2019\/06\/web-lg-fs1-logo.png","width":1341,"height":1098,"caption":"Flagship One, Inc."},"image":{"@id":"https:\/\/www.fs1inc.com\/blog\/#\/schema\/logo\/image\/"},"sameAs":["https:\/\/www.facebook.com\/flagshipone","https:\/\/x.com\/theflagshipone","https:\/\/www.instagram.com\/flagship_one","https:\/\/www.youtube.com\/channel\/UC0oyKphffBM2qkJ-gKPmMXw"]},{"@type":"Person","@id":"https:\/\/www.fs1inc.com\/blog\/#\/schema\/person\/a3cf463514bd03eb7656953ef8f75700","name":"FlagshipOne","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/secure.gravatar.com\/avatar\/351b81e51993825aea73280c48061a7205fdd2189730ebbdee5d63894c5cebb4?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/351b81e51993825aea73280c48061a7205fdd2189730ebbdee5d63894c5cebb4?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/351b81e51993825aea73280c48061a7205fdd2189730ebbdee5d63894c5cebb4?s=96&d=mm&r=g","caption":"FlagshipOne"},"description":"The world's top supplier of programmed OEM (Original Equipment Manufacturer) Powertrain Control Modules (PCM), Engine Control Modules (ECM), Injection Control Modules (IDM), Body Control Modules (BCM), Transmission Control Modules (TCM), Engine Control Units and all other car control units. With over a decade in the business, we are the most reliable source when it comes to programming services for replacement engine control modules.","sameAs":["https:\/\/www.fs1inc.com\/","https:\/\/www.facebook.com\/flagshipone\/","https:\/\/www.instagram.com\/flagship_one\/","https:\/\/www.linkedin.com\/company\/fs1inc"],"url":"https:\/\/www.fs1inc.com\/blog\/author\/flagship1inc\/"}]}},"_links":{"self":[{"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/posts\/527200","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/comments?post=527200"}],"version-history":[{"count":1,"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/posts\/527200\/revisions"}],"predecessor-version":[{"id":527201,"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/posts\/527200\/revisions\/527201"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/media\/522188"}],"wp:attachment":[{"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/media?parent=527200"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/categories?post=527200"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/tags?post=527200"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}