Editing On-board diagnostics (section)

===ALDL===

{{Main|ALDL}}

GM's [[ALDL]] (Assembly Line Diagnostic Link) is sometimes referred to as a predecessor to, or a manufacturer's proprietary version of, an OBD-I diagnostic starting in 1981. This interface was made in different varieties and changed with power train control modules (aka PCM, ECM, ECU). Different versions had slight differences in pin-outs and baud rates. Earlier versions used a 160 baud rate, while later versions went up to 8192 baud and used bi-directional communications to the PCM.<ref>{{Citation |title=ALDL Bluetooth AdapterUser's Guide |publisher=1320 Electronics LLC }}</ref><ref>{{Cite web|url=http://www.techedge.com.au/vehicle/aldl160/160serial.htm|title = Reading GM's 160 baud ALDL Data Stream with a Standard PC Serial Port}}</ref>