Dodge Dakota 2001, Service Manual

Page: 485 / 2307

(6) Install the headliner onto the roof panel. Refer
to Headliner in the Removal and Installation sec-
tion of Body for the procedures.
(7) Install the overhead console onto the overhead
console bracket. Refer to Overhead Console in the
Removal and Installation section of this group for the
procedures.
(8) Reconnect the battery negative cable.
SPECIAL TOOLS
OVERHEAD CONSOLE SYSTEMS
COMPASS/MINI-TRIP
COMPUTER
DESCRIPTION
The compass mini-trip computer is located in the
overhead console on models equipped with this
option. The compass mini-trip computer units include
the electronic control module, a Vacuum-Fluorescent
Display (VFD), a compass sensor unit and two push
button function switches.
The compass mini-trip computer module contains a
central processing unit and interfaces with other
electronic modules in the vehicle on the Programma-
ble Communication Interface (J1850) data bus net-
work. The J1850 data bus network allows the
sharing of sensor information. This helps to reduce
wire harness complexity, reduce internal controller
hardware, and reduce component sensor current
loads. At the same time, this system provides
increased
reliability, enhanced diagnostics, and
allows the addition of many new feature capabilities.
The compass mini-trip computer provides several
electronic functions and features. Some of the func-
tions and features that the compass mini-trip com-
puter module supports and/or controls, include the
following display options:
•
Compass and temperature - provides the out-
side temperature and one of eight compass readings
to indicate the direction the vehicle is facing.
•
Trip odometer (TRIP ODO) - shows the dis-
tance travelled since the last trip computer reset.
•
Average fuel economy (AVG ECO) - shows
the average fuel economy since the last trip computer
reset.
•
Instant fuel economy (ECO) - shows the
present fuel economy based upon the current vehicle
distance and fuel used information.
•
Distance to empty (DTE) - shows the esti-
mated distance that can be travelled with the fuel
remaining in the fuel tank. This estimated distance
is computed using the average miles-per-gallon from
the last 30 gallons of fuel used.
•
Elapsed time (ET) - shows the accumulated
ignition-on time since the last trip computer reset.
•
Blank screen - the compass mini-trip VFD is
turned off.
The ambient temperature sensor is hard wired to
the HVAC control head. Data input for all other com-
pass mini-trip computer functions, including VFD
dimming level, is received through J1850 data bus
messages. The compass mini-trip computer uses its
internal programming and all of these inputs to cal-
culate and display the requested data. If the data
displayed is incorrect, perform the self-diagnostic
tests as described in this group. If these tests prove
inconclusive, the use of a DRB scan tool and the
proper Diagnostic Procedures manual are recom-
mended for further testing of the compass mini-trip
computer module and the J1850 data bus.
The compass mini-trip computer module cannot be
repaired, and is available for service only as a unit.
This unit includes the push button switches and the
plastic module and display lens. If any of these com-
ponents is faulty or damaged, the complete compass
mini-trip computer module must be replaced.
COMPASS
While in the compass/temperature mode, the com-
pass will display the direction in which the vehicle is
pointed using the eight major compass headings
(Examples: north is N, northeast is NE). The self-cal-
ibrating compass unit requires no adjusting in nor-
mal use. The only calibration that may prove
necessary is to drive the vehicle in three complete
circles, on level ground, in not less than forty-eight
seconds. This will reorient the compass unit to its
vehicle.
The compass unit also will compensate for magne-
tism the body of the vehicle may acquire during nor-
mal use. However, avoid placing anything magnetic
directly on the roof of the vehicle. Magnetic mounts
for an antenna, a repair order hat, or a funeral pro-
cession flag can exceed the compensating ability of
the compass unit if placed on the roof panel. Mag-
netic bit drivers used on the fasteners that hold the
overhead console assembly to the roof header can
also affect compass operation. If the vehicle roof
Degaussing Tool 6029
8M - 6 MESSAGE SYSTEMS
AN
OVERHEAD CONSOLE (Continued)