{"id":425,"date":"2012-06-14T20:47:00","date_gmt":"2012-06-14T20:47:00","guid":{"rendered":"http:\/\/3.68.38.87\/?p=425"},"modified":"2023-06-01T03:28:14","modified_gmt":"2023-06-01T03:28:14","slug":"fun-diagnostic-services","status":"publish","type":"post","link":"https:\/\/canbushack.com\/web\/fun-diagnostic-services\/","title":{"rendered":"FUN DIAGNOSTIC SERVICES!"},"content":{"rendered":"\n<p>Some services are boring.. like really, really, really, boring.. but others can make the car move gauges or make the car\u2019s warning lights light up.&nbsp; Here is a bit more about these types of services.<\/p>\n\n\n\n<p><strong><br>Stop Normal Communications (GMLAN and Others)<\/strong>:<br>This service is fun because you can make the Normal Communications (the ECU to ECU communications that occurs normally on the network) stop.&nbsp; Why would such a service exist, mostly to clear the bus for large amounts of data such as when a controller is going to be reflashed over the CAN Bus.&nbsp; On GMLAN this service is 0x28.&nbsp; It does not require any sub-function so an example of this might be:&nbsp;0x7E0 01 28 00 00 00 00 00 00.&nbsp;This will command the engine controller to stop sending normal communications.&nbsp; Of course you don\u2019t ever want to do this while the car is being driven, but it\u2019s pretty fun to see what happens when you do it!<\/p>\n\n\n\n<p>You will see the Engine Controllers Normal messages virtually disappear.&nbsp; I say virtually because not all messages will go away, some that are mission critical will stay, but a lot of them will not.<\/p>\n\n\n\n<p>This service can also be useful if you want to simulate the messages the ECU would send without removing the power to the controller or cutting the CAN Bus itself.<\/p>\n\n\n\n<p>This service requires that you continually send a Tester Present (0x3E) message periodically (2 seconds is good) in order to maintain this.&nbsp; If you want to return the communications send a Return to Normal message (0x20):&nbsp;0x7E0 01 20 00 00 00 00 00 00.&nbsp; This will restore communications.&nbsp; Or simply stop sending the Tester Present message and it will automatically restore communications after 3 seconds. Oh what fun you\u2019ll have.<\/p>\n\n\n\n<p><strong>Input\/Output Control (ISO 14229 \u2013 UDS)<\/strong>:<br>This is pretty much the coolest services ever made.&nbsp; I\/O Control is exactly as it sounds, you can command Outputs on the Module to do your bidding.&nbsp; Of course software control will limit your bidding to a safe and secure bidding, but it\u2019s still cool.<\/p>\n\n\n\n<p>I\/O Control (Service 0x2F) requires 3 parameters: a DID (Data ID), Control Record, and Control Mask.&nbsp; The DID is a two byte ID for the output (or input) you want to modify.&nbsp; Control Record is what you want the output to do (On\/Off, Up\/Down, etc.). Control Mask is a bitwise mask of one or more parameters that will be modified.&nbsp; An Example of a I\/O Control is something like this: 0x7E0 06 2F 11 22 07 01 00 00 00.&nbsp; Where 0x1122 is the DID, 0x07 is the Control Record, and 0x0100 is the mask.&nbsp; This is not a real function, but you could potentially iterate through all possibilities and wait for the controller to give you a positive response.&nbsp; It would take a while, but it\u2019d be interesting to see what happened\u2026. Right!?<\/p>\n\n\n\n<p>It\u2019s likely that you will get a negative response from the controller&nbsp;0x7E8 03 7F 2F 13 00 00 00 00, where 0x13 is the Negative Response Code (NRC).<\/p>\n\n\n\n<p><strong>Here are a few possible NRCs you may receive<\/strong>:<\/p>\n\n\n\n<p>\u2022&nbsp;&nbsp;&nbsp; 0x13 \u2013 Incorrect Message Length or Invalid Format.<br>\u2022&nbsp;&nbsp;&nbsp; 0x22 \u2013 Condition Not Correct.<br>\u2022&nbsp;&nbsp;&nbsp; 0x31 \u2013 Request Out of Range.<br>\u2022&nbsp;&nbsp;&nbsp; 0x33 \u2013 Security Access Denied.<br>\u2022&nbsp;&nbsp;&nbsp; 0x80-0xFF \u2013 OEM Specific.<\/p>\n\n\n\n<p>Good luck\u2026\u2026. .. have fun ..<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Some services are boring.. like really, really, really, boring.. but others can make the car move gauges or make the car\u2019s warning lights light up.&nbsp; Here is a bit more about these types of services. Stop Normal Communications (GMLAN and Others):This service is fun because you can make the Normal Communications (the ECU to ECU [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":376,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[7],"tags":[],"class_list":["post-425","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"_links":{"self":[{"href":"https:\/\/canbushack.com\/web\/wp-json\/wp\/v2\/posts\/425","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/canbushack.com\/web\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/canbushack.com\/web\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/canbushack.com\/web\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/canbushack.com\/web\/wp-json\/wp\/v2\/comments?post=425"}],"version-history":[{"count":0,"href":"https:\/\/canbushack.com\/web\/wp-json\/wp\/v2\/posts\/425\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/canbushack.com\/web\/wp-json\/wp\/v2\/media\/376"}],"wp:attachment":[{"href":"https:\/\/canbushack.com\/web\/wp-json\/wp\/v2\/media?parent=425"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/canbushack.com\/web\/wp-json\/wp\/v2\/categories?post=425"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/canbushack.com\/web\/wp-json\/wp\/v2\/tags?post=425"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}