Vw online technical library - diagnostic trouble codes, Search: this is about a 35 page table. you may want to search for the dtc you need using your browser's "find" feature. (often this is under the 'edit' menu / 'find. Welcome guzzle' diagnostic trouble code list web page, Obd-ii diagnostic trouble codes (dtc) has four basic code categories: p - powertrain c - chassis b - body u - future diagnotic systems a breakdown of these categories. Jeep grand cherokee wj - diagnostic trouble codes, A diagnostic trouble code (dtc) indicates that the powertrain control module (pcm) has recognized an abnormal condition in the system. dtc's are the results of a.