GM used 12 position Delphi Packard 12020043 ALDL diagnostic sockets on most US market vehicles from 1982-1994.Further instructions and flash/blink code definitions by year/make/model here.jumper ALDL jack terminals A & B with a piece of stiff wire or an ALDL Test Key. NOTE: This will not work with 1994 & 1995 OBD 1.5 jacks if it reliably lights during the bulb check, when the ignition is switched on, this method can probably be used.

SES (Service Engine Soon) MIL (Malfunction Indicator Lamp) CEL (Check Engine Lamp) these acronyms all refer to the same lamp. The diagnostic lamp is called several different things. 8192 Baud bi-directional TTL serial data RX & TX I would be sorely tempted to install the old ALDL jack if I owned a 1995 GM. This looks like 1996 and later J1962 OBD II jacks because it is physically the same jack. Not all positions are populated on all vehicles and usually only one serial data line is present. CLCC (If used) 160 Baud Serial Data TX only (1982-1986 Carburettor Trucks) Repair parts Delphi 12020043 ALDL Jack with 15484100 FEM METRIPAK 280 18AWG Au PLTD terminals.

there seem to be more poorly constructed Chinese knockoffs than the real thing now and they are priced the same or more. If I could afford a real Vertronix or HP Tech II I don't feel confident that I could weed out the Chinese counterfeits. Most of us can't afford a real Tech II and those are getting scarce. The Tech I is all but extinct (I haven't seen one for sale in over 2 years). If you can find a working Tech I or a real Tech II they can have more functionality than any aftermarket solution depending on your needs. Mr Goodwrench used the Tech I and later the Tech II to communicate with these vehicles. OBD 1 was the 1991 California stab at standardization of automotive diagnostics prior to Federal adoption of the much more comprehensive SAE OBD II standards. It varied greatly by model, nameplate, year, and even engine choice.ĪLDL is not always OBD 1 but OBD 1 was ALDL. It was not standardized even loosely within GM divisions. or at least a whack at it.ĪLDL is an acronym that means Assembly Line Diagnostic Link It's a proprietary GM PWM TTL level Serial communications protocol.

PC hardware and software for diagnostic code reading and real-time data logging on the cheap.

Gm obd1 diagnostic software