Vehicle speed
Vehicle speed |
The ABS electronic control module sends a speed signal to pin 39 of the Trionic electronic control module. This signal is a square wave which varies between 0 V and B+ 29 times per wheel revolution. This speed signal is used to:
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determine which gear is engaged
at the time
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activate the SHIFT UP lamp (does not apply to 5th gear)
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• |
limit the boost pressure in Reverse, 1st and 2nd gears
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activate fuel shut-off in 3rd, 4th and 5th gears
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• |
activate speed limitation (by limiting the boost pressure at 230
km/h)
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prevent adaptation of idle speed control when the car is in motion. In the
absence of a speed signal the above functions are not performed and, on cars with a manual
gearbox, boost pressure is limited.
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