Centrodyne S620 - SILENT 610;620 SPEED SIGNAL JUMPER SELECTION; To change the speed signal jumper

SILENT 610/620
SPEED SIGNAL JUMPER SELECTION
Speed signals will generally be of two types, 1) digital or 2) analog.
1. Digital speed signals provide an on/off, high/low signal. Mechanical transducers on speedo cables
usually provide a digital signal, and in general, speed signals provided by the vehicle computer (ECM) are
also digital (Example – Caprice and most GM Vehicles).
2. Analog speed signals vary in amplitude and frequency at different speeds. Analog speed signals are
usually provided by a magnetic speed sensor in the transmission (Example - Crown Victoria and most
Ford Vehicles).
To change the speed signal jumper:
1) Remove the front sealing screw and the two screws on the back of the taximeter.
2) Slide the front face and printed circuit boards out of the case.
3) Locate the corner of the board where the jumpers are located and carefully remove the jumpers
and re-install as illustrated below.
JP2
For digital speed signal input, (square wave) place
j
umpers so that the pins in position A & B and A & B
are connected.
For analog speed signals, (magnetic pick-up) place
j
umpers so that the pins in position B & C and B & C
are connected.
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