thanks all;
and ymz, for the Vortex thread, was very informative with definitive guides, photo's, Dx/Tx, brake-light switch innards, DOT complaints, recalls, etc as the blinking glow plug icon +/- no brake lights/cruise/limp mode... as it evolved over the last ten years; and culminating finally in a new design with simple install (Green 1C0 945 511 A NAR) that I bought this AM; leave pedal as is, lube tip, push in to match ears, twist clock-wise until click (allows nubs to push contact arms and supposedly set plunger to correct distance)
Bought two at $3.75 each; cleared the brake-light fault code (implausible value or whatever) with VAG-COM 504 (connected by 2x25ft serial cables to the old ASUS P2B computer with a serial port--as the serial header on the premium Gigabyte GA-X38-DQ6 MotherBoard [especially purchased for the serial and parallel headers and then a pain to find a serial/parallel bracket and cables to the headers]...would not work (evidently a non standard pin-out to be sorted out some day).
Our Vehicle NB 2001 TDI.
Our problem by the way, was wife called with blinking glow plug light yesterday on way home from Intel, and mentioned on arrival home that cruise control was not working.
Brake lights worked, fuses intact, no LED's (though have some but were not bright enough); owner manual useless>>take to dealer with no list of causes/possibilities; don't know where I put the Bentley's CD; VW NB Service Manual 98,99 (paper) no help;
did not feel like setting up the old system, so looked here.
Switch (Lavender 1J0 945 511D) pins 1-4 with continuity, but not with pins 2-3 (to ECU); took apart: 1-4 contact burned/pitted but functional. 2-3 contact arm was not touching contact as cracked near base and then fell off when examined....hence down to Armstrong for hopefully the new improved version..and that is what they had.
So now was semi-forced to hook up the old BORG system and string out the serial cable to reset the fault code(s); looked up on Ross-Tech and now see that is up to version 10.6 from my 504.1.
All seems back to normal and have a spare...
Thanks all