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XJ VEHICLE SPEED CONTROL SYSTEM 8H - 1
VEHICLE SPEED CONTROL SYSTEM
CONTENTS
page
GENERAL INFORMATION
INTRODUCTION ......................... 1
GENERAL INFORMATION
INTRODUCTION
This group covers both Left-Hand Drive (LHD) and
Right-Hand Drive (RHD) versions of this model.
Whenever feasible, the RHD versions of affected
vehicle components have been constructed as mirrorimage of the LHD versions. While most of the illustrations used in this group represent only the LHD
version, the diagnostic and service procedures outlined can generally be applied to either version.
Exceptions to this rule have been clearly identified as
LHD or RHD, if a special illustration or procedure
was/is required.
Features unique to the diesel engine will be covered in this section.
• Models equipped with the 2.5L diesel engine do
not use a vacuum reservoir to retain engine vacuum
for speed control operation. There are no vaccum-operated speed control servos used in vehicles with the
2.5L diesel engine.
• The range of the speed control system operation
is restricted to speeds between 56 km/h (35 MPH) to
145 km/h (90 MPH).
• Inputs to the MSA that allow speed control operation are from the vehicle speed sensor and the
Speed Control Switch.
• Two separate speed control switch modules are
mounted on the steering wheel to the left and right
side of the driver’s airbag module. Switch features
are:
• Within the two switch modules, five momen-
tary contact switches, supporting seven different
speed control functions are used. The outputs from
these switches are filtered into one input. The MSA
determines which output has been applied through
resistive multiplexing. The input circuit voltage is
measured by the MSA to determine which switch
function has been selected.
• A speed control indicator lamp, located on the
instrument panel cluster is energized by the MSA via
the CCD Bus. This occurs when speed control system
power has been turned ON, and the engine is running.
• The two switch modules are labeled: ON/OFF,
SET, RESUME/ACCEL, CANCEL and COAST. Refer
to the owner’s manual for more information on speed
control switch functions and setting procedures. The
individual switches cannot be repaired. If one individual switch fails, the switch module must be
replaced.
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