Hi my name is Dan.
February 1994 and Later -
The speedo/tach cluster has two sets of DIP switches with eight switches in
each bank. The DIP switches are located at the top, rear of the cluster and can
be used to manually program speedo/tach module information ( Figure 17 ).
IMPORTANT: The original speedo/tach
cluster microprocessor is electronically programmed, when the vehicle is built,
to match the component configuration of the vehicle. However, the physical
positions of all the DIP switches remain in the "0" position.
The original electronically programmed settings are shown on the vehicle
linesetting ticket in the 010000 code, Speedo & Misc - last sixteen (16)
digits ( Figure 18 ), and on a label attached
to the top of the original cluster ( Figure 19
DIP switch settings can also be determined by following the DIP Switch Configuration section.
IMPORTANT: Physically moving any of the
DIP switches from the "0" position disables all of the electronically programmed
settings of the cluster. If any DIP switch is moved for any reason, then ALL of
the DIP switches must be physically moved to the appropriate positions shown on
the vehicle linesetting ticket, or the label attached to the top of the cluster.
Physically moving all the DIP switches back to the "0" position of an
electronically programmed cluster will enable the original programmed settings.
Any changes in vehicle components like tire size or axle ratio requires
recalibration of the speedometer. The prop shaft revolutions per mile must be
calculated and the DIP switches physically set. Refer to PROGRAMMING, CALCULATION AND SWITCH
NOTE: Physically setting the new DIP
switch settings for the speedometer disables all of the electronically
programmed settings. This requires that the rest of the switches also be
physically set to the positions shown on the vehicle linesetting ticket, the
cluster label, or can be determined by following the DIP Switch Configuration section.
Replacing the speedo/tach cluster requires that the new module be manually
programmed by physically setting all DIP switches to match the vehicle component
The original DIP switch settings are found on the vehicle linesetting ticket,
on the label attached to the top of the original cluster, or can be determined
by following the DIP Switch Configuration section below.
DIP Switch Configuration - Speedometer
DIP Switch Configuration - Speedometer - Programming the speedometer DIP
switches involves setting the first ten (10) switches (Number 1 thru 8 on left
plus 1 and 2 on right bank) to positions based on the revolutions per mile of
the propeller shaft. Refer to PROGRAMMING, CALCULATION AND SWITCH SETTING .
DIP Switch Configuration - Two Speed Axle Ratio
- The number three
switch position on the right bank is for calibration of the two available
two-speed axle ratios. This switch position is "0" for a 1.36:1, or "1" for a
1.39:1 axle ratio.
To calculate two-speed axle ratio, divide the high speed gear ratio by the
low speed gear ratio. These ratios are stamped into a tag located on the
differential carrier. This switch is not active if not equipped with a two-speed
axle and the lineset ticket or cluster label will be marked with an "*".
DIP Switch Configuration - Tachometer
- The number 4, 5, and 6
switch positions on the right bank are for programming the tachometer RPM
settings. These settings are based on engine model and flywheel gear teeth per
revolution and are shown in the Tachometer DIP Switch Settings Chart.
Tachometer DIP Switch Settings Chart
Teeth Per Revolution
Engine or Output
Cummins B (Export) (C92 Rev.)
DIP Switch Configuration - Tachometer Range
- The number seven
switch is to set the tachometer range scale. This switch is always set to the
"0" position for 0-3500 RPM readings.
DIP Switch Configuration - Odometer
- The number 8 switch on the
right bank is for setting the odometer to show either miles or kilometers. This
switch must be set to "0" for miles, or "1" for kilometers.