I want to read any fault codes stored in my 1992 Volvo 940's ABS module. I've tried the procedure described in the popular 700/900 series FAQ700/900 series FAQ without success. That procedure involves plugging the car's OBD lead into a numbered port, pushing a button, and reading the code as a series of flashes of an LED in the engine compartment. The linked FAQ instructions have me plug the diagnostic lead into box A, position 3. (Positions 2 and 6 are for the fuel and ignition systems’ onboard diagnostic, the so-called OBD-1.) However, I could get no codes to appear — not even code 1-1-1 for "everything is fine."
The only other diagnostic lead position available is Box B, position 2. (Every other position is just a blank hole.) Plugging into B-2 yielded a code, but I have no information that confirms whether it's the ABS module or something else.
Does anyone know the procedure for reading the ABS diagnostic codes? Perhaps someone with a copy of the relevant factory service manual (green book)?