{"id":13023,"date":"2020-04-15T12:29:32","date_gmt":"2020-04-15T16:29:32","guid":{"rendered":"https:\/\/techlink.mynetworkcontent.com\/?p=13023"},"modified":"2020-04-15T12:29:32","modified_gmt":"2020-04-15T16:29:32","slug":"unable-to-deactivate-brake-boost-system","status":"publish","type":"post","link":"https:\/\/gm-techlink.com\/?p=13023","title":{"rendered":"Unable to Deactivate Brake Boost System"},"content":{"rendered":"<p class=\"western\"><span style=\"font-size: 12pt;\">A GDS2 error message stating \u201cRequest Rejected by the Control Module\u201d may occur when trying to deactivate the brake boost system while performing the hydraulic brake system bleeding procedure on some 2019-2021 XT4 models. (Fig. 15)<\/span><\/p>\n<p class=\"western\">\n<p class=\"western\" style=\"text-align: center;\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-13011\" src=\"https:\/\/techlink.mynetworkcontent.com\/wp-content\/uploads\/2020\/04\/F15-brake-1.png\" alt=\"\" width=\"740\" height=\"482\" srcset=\"https:\/\/gm-techlink.com\/wp-content\/uploads\/2020\/04\/F15-brake-1.png 740w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2020\/04\/F15-brake-1-300x195.png 300w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2020\/04\/F15-brake-1-84x55.png 84w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2020\/04\/F15-brake-1-200x130.png 200w\" sizes=\"auto, (max-width: 740px) 100vw, 740px\" \/><span style=\"font-size: 12pt;\"><b>Fig. 15<\/b><\/span><\/p>\n<p class=\"western\">\n<p class=\"western\"><span style=\"font-size: 12pt;\">The error message may be caused by the B20 Brake Fluid Level Switch Connector and the B34D Engine Coolant Temperature Sensor 4 Connector being swapped during reassembly.<\/span><\/p>\n<p class=\"western\"><span style=\"font-size: 12pt;\">If these connectors are swapped, DTC C0049 (<span style=\"color: #000000;\"><span style=\"font-family: Verdana, serif;\">Low Brake Fluid Indicated<\/span><\/span>) SYM05 (<span style=\"color: #000000;\"><span style=\"font-family: Verdana, serif;\">High Voltage\/Open<\/span><\/span>) will be stored in the Electronic Brake Control Module (EBCM) and P2AFF (<span style=\"color: #000000;\"><span style=\"font-family: Verdana, serif;\">Engine Coolant Temperature Sensor 4 Circuit High Voltage) <\/span><\/span>will be stored in the Engine Control Module (ECM).<\/span><\/p>\n<p class=\"western\"><span style=\"font-size: 12pt;\">When connecting the Brake Fluid Level Switch (Fig. 16) and Engine Coolant Temperature Sensor 4 (Fig 17), be sure to verify that the connectors are in the correct location. Reverse the connections if necessary.<\/span><\/p>\n<p class=\"western\">\n<p class=\"western\" style=\"text-align: center;\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-13012\" src=\"https:\/\/techlink.mynetworkcontent.com\/wp-content\/uploads\/2020\/04\/F16-brake-2.png\" alt=\"\" width=\"740\" height=\"481\" srcset=\"https:\/\/gm-techlink.com\/wp-content\/uploads\/2020\/04\/F16-brake-2.png 740w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2020\/04\/F16-brake-2-300x195.png 300w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2020\/04\/F16-brake-2-85x55.png 85w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2020\/04\/F16-brake-2-200x130.png 200w\" sizes=\"auto, (max-width: 740px) 100vw, 740px\" \/><span style=\"font-size: 12pt;\"><b>Fig. 16<\/b><\/span><\/p>\n<p class=\"western\">\n<p class=\"western\" style=\"text-align: center;\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-13013\" src=\"https:\/\/techlink.mynetworkcontent.com\/wp-content\/uploads\/2020\/04\/F17-brake-3.png\" alt=\"\" width=\"740\" height=\"480\" srcset=\"https:\/\/gm-techlink.com\/wp-content\/uploads\/2020\/04\/F17-brake-3.png 740w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2020\/04\/F17-brake-3-300x195.png 300w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2020\/04\/F17-brake-3-85x55.png 85w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2020\/04\/F17-brake-3-200x130.png 200w\" sizes=\"auto, (max-width: 740px) 100vw, 740px\" \/><span style=\"font-size: 12pt;\"><b>Fig. 17<\/b><\/span><\/p>\n<p class=\"western\">\n<p class=\"western\"><span style=\"font-size: 12pt;\"><i>&#8211; Thanks to Calvin Kohring<\/i><\/span><\/p>\n","protected":false},"excerpt":{"rendered":"<p>A GDS2 error message stating \u201cRequest Rejected by the Control Module\u201d may occur when trying to deactivate the brake boost system while performing the hydraulic brake system bleeding procedure on [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-13023","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/posts\/13023","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=13023"}],"version-history":[{"count":1,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/posts\/13023\/revisions"}],"predecessor-version":[{"id":13024,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/posts\/13023\/revisions\/13024"}],"wp:attachment":[{"href":"https:\/\/gm-techlink.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=13023"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=13023"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=13023"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}