Jamar RAC Plus I, User Manual

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2-13
Step 2 – Attaching the Magnetic Sensor
The Magnetic Sensor (F) is mounted
directly over the magnets as shown in
figure 3. When the wheel or drive shaft
begins turning, a speed impulse is sent
to the DMI every time a magnet passes
by the tip of the speed sensor. For the
speed sensor to operate properly, the
spacing between the magnets and the
tip of the sensor must always remain
constant. Before permanently mounting
any parts, be sure that the location you
have selected will meet the requirements
shown in Figure 7. NOTE: Observe
magnet polarities (see previous section).
Using the Sensor Bracket (D) provided, locate a nut or bolt on the side of
the transmission, close to the magnets. Attach the bracket to the trans-
mission using the hardware . (You may have to drill a larger hole in the
sensor bracket to allow proper fitting over the selected bolt/stud.) Bend
the bracket as required so that the Sensor is scanning the targets with a
spacing of about ¼ to ½ inch. The cable coming from the Magnetic Sen-
sor will be used as part of the next step.
Step 3 - Installing and
Wiring the Terminal Block
Mount the Terminal Block (H)
provided with the Vehicle Instal-
lation Kit under the dash inside
the vehicle, if possible. If it is not
possible to mount it inside the
vehicle, mount on the driver’s
side fender well or other con-
venient location. The terminal
block can be mounted using the
Velcro provided.
The Magnetic Sensor cable has
5 feet of a jacketed 3 wire cable
45" max.
3/8" nuts
Sensor
(Green body)
1/4" to 1/2" air gap
Fig. 2-16
Sensor assembly
must not be mounted
more than 45 from
perpendicular
To Figure 8
Black
Yellow
Green
Red
Red
White
Black
Instrument Connector
Firewall
Ground
+12
VDC
Red
Fig. 2-17
fuse
Instrument black wire to battery ground and sensor black wire.
Instrument yellow wire to b12 VDC and sensor white wire.
Instrument green wire to sensor red wire.
Instrument red wire not used.
If possible, mount Ter-
minal Block under dash
inside vehicle. Otherwise,
mount under hood in
convenient location (left
fender well) to accommo-
date necessary wiring.
Chapter 2 — Installation