RAC Plus I User’s Manual
2-2
Before You Begin
The JAMAR RAC Plus I distance measuring instruments are very reliable.
However, there can be some external variables that could affect proper op-
eration and the ability to accurately measure distance traveled. By observing
a few simple precautions you will be able to eliminate potential problems.
• Do not install wires near any object that could cause stray pulses to
be picked up, such as the alternator, spark plugs or engine coil.
• Do not install the wires or sensor near any objects that will get hot,
such as the manifold. The installation wires or sensor can melt if they
are too close to a heat source.
• Do not install wires near any objects that could vibrate and cut the
wires.
• Tire pressure should be the maximum suggested by the tire manu-
facturer, typically 32-35 PSI cold. The tire should have ample tread
depth. Steel belted radial tires are highly recommended.
• Drive the vehicle 3 to 5 miles (depending on climate) to warm the
tires up to normal operating temperatures prior to calibrating your RAC.
Refer to Chapter 3, Calibration for more detailed instructions.