Dakota Digital VHX-84B-REG VHX-84B-REG-S-W, Manual

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MAN 650314:D 16
Auto Cal ( AUTO )
This menu is used to calibrate the speed signal by driving a measured mile. Start this
procedure with the vehicle stopped at the beginning of a known measured mile. Shut the car off,
press and hold SW1 and turn the key on and start the car then release the switch to get into
setup once the car is running. Then select the speed setup menus.
When “
speed AUTO
” is displayed press and hold SW1 until you get “
SPD Pulses 0
”
Release SW1 and the speed/LCD1 message display should read “ SPD Pulses 0 ”, LCD2
will read “
Setup
”. The other gauges should display the current readings (tach, fuel,
volt, water, and oil). Stopped at the beginning of the measured mile, the “
SPD Pulses
0 ” reading should stay at “ 0 ” until you start driving. If this is number is increasing while
stopped, you have something wired wrong or are picking up interference; please check
connections and wire routing before continuing or you will have incorrect readings later.
Begin driving the measured mile.
The “
SPD Pulses x ” reading should start to increase as you travel, indicating the pulses
received from the speed sensor or VSS. This is known as the pulses per mile (PPM).
The acceptable range for this is about 2,000 – 250,000.
Once you reach the end of the marked mile, or are passing the marker, press and release
SW1. The readings will zero out, then everything should move up to the correct values
and the speedometer should now be displaying your current speed.
Auto Cal is now complete and your speedometer should be reading correctly.
NOTES: You do not have to drive at a constant speed nor do you have to avoid stopping
during Auto Cal. When completed, you do not need to stop; you may, but you can also
just press and release SW1 as you pass the one mile mark.
The message display cannot be used to determine when the mile has been driven; it’s only
there as a reference to indicate pulses are coming into the control box. Even if you have
an 8,000 PPM sensor you may calibrate at 9xxx PPM (for example) due to gearing and tire
size.
Also be aware that the odometer is calculated from the speedometer cal value; if it is not
calibrated properly, the odometer reading could be higher/lower than actual.
***If you do not receive more than 2,000 pulses during calibration the unit will error out
and display a brief “
pulse to low
pulse to low pulse to low
pulse to low ” message and revert to a default PPM setting.
Adjust Mode (
ADJUST )
Adjust is slightly different depending on what your input signal is selected to in the
SENDER menu.
When “ adjust ” is displayed, press and hold SW1 until the message screen changes.
Release SW1.
If “ normal
”
is selected for the sender type, it will allow you to adjust the signal that is
being supplied to the SPD SND terminal coming from a pulse generator or ECU. The fuel, volt,
oil, water, and tach will operate normally. The speedometer will show the speed reading and the
speed/LCD1 message display will say “
xx ADJ MPH ”. Begin driving at a known speed. Press
and hold SW1 to increase the speedometer reading, the next press and hold of SW1 will
decrease the speedometer reading. You can continue adjusting up and down as needed until the
reading is correct. When the speedometer is correct, stop and restart the system, by turning the
key/power off and then starting the vehicle back up. The new calibration will be saved when the
there is no switch press for eight seconds.