CRUISE INDICATOR
DESCRIPTION
A cruise indicator is standard equipment on all
instrument clusters (Fig. 11). However, on vehicles
not equipped with the optional speed control system,
this indicator is electronically disabled. The cruise
indicator is located near the upper edge of the instru-
ment cluster, to the left of center. The cruise indica-
tor consists of a stencil-like cutout of the word
“CRUISE” in the opaque layer of the instrument
cluster overlay. The dark outer layer of the overlay
prevents the indicator from being clearly visible
when it is not illuminated. A green Light Emitting
Diode (LED) behind the cutout in the opaque layer of
the overlay causes the “CRUISE” text to appear in
green through the translucent outer layer of the
overlay when the indicator is illuminated from
behind by the LED, which is soldered onto the
instrument cluster electronic circuit board. The illu-
mination intensity of the cruise indicator is one-step
dimmable. When the exterior lighting is turned On,
the indicator is dimmed; and, when the exterior
lighting is turned Off, the indicator is illuminated at
full intensity. The cruise indicator is serviced as a
unit with the instrument cluster.
OPERATION
The cruise indicator gives an indication to the vehi-
cle operator when the speed control system is turned
On, regardless of whether the speed control is
engaged. This indicator is controlled by the instru-
ment cluster circuit board based upon cluster pro-
gramming and electronic messages received by the
cluster from the Powertrain Control Module (PCM)
over the Programmable Communications Interface
(PCI) data bus. The cruise indicator Light Emitting
Diode (LED) is completely controlled by the instru-
ment cluster logic circuit, and that logic will only
allow this indicator to operate when the instrument
cluster receives a battery current input on the fused
ignition switch output (run-start) circuit. Therefore,
the LED will always be off when the ignition switch
is in any position except On or Start. The LED only
illuminates when it is provided a path to ground by
the instrument cluster transistor. The instrument
cluster will turn on the cruise indicator for the fol-
lowing reasons:
• Cruise Lamp-On Message - Each time the
cluster receives a cruise lamp-on message from the
PCM indicating the speed control system has been
turned On, the cruise indicator is illuminated. The
indicator
remains
illuminated
until
the
cluster
receives a cruise lamp-off message from the PCM or
until the ignition switch is turned to the Off position,
whichever occurs first.
• Actuator Test - Each time the cluster is put
through the actuator test, the cruise indicator will be
turned on, then off again during the bulb check por-
tion of the test in order to confirm the functionality
of the LED and the cluster control circuitry.
The PCM continually monitors the speed control
switches to determine the proper outputs to the
speed control servo. The PCM then sends the proper
cruise indicator lamp-on and lamp-off messages to
the instrument cluster. For further diagnosis of the
cruise indicator or the instrument cluster circuitry
that controls the indicator, (Refer to 8 - ELECTRI-
CAL/INSTRUMENT CLUSTER - DIAGNOSIS AND
TESTING). For proper diagnosis of the speed control
system, the PCM, the PCI data bus, or the electronic
message inputs to the instrument cluster that control
the cruise indicator, a DRBIII
t scan tool is required.
Refer to the appropriate diagnostic information.
ENGINE TEMPERATURE
GAUGE
DESCRIPTION
An engine coolant temperature gauge is standard
equipment on all instrument clusters. The engine
coolant temperature gauge is located in the lower
right quadrant of the instrument cluster, below the
oil pressure gauge. The engine coolant temperature
gauge consists of a movable gauge needle or pointer
controlled by the instrument cluster circuitry and a
fixed 90 degree scale on the cluster overlay that
reads left-to-right from 40° C (or 100° F) to 125° C
(or 260° F). An International Control and Display
Symbol icon for “Engine Coolant Temperature” is
located on the cluster overlay, directly above the hub
of the gauge needle (Fig. 12). The engine coolant tem-
perature gauge graphics are white and blue against a
black field except for a single red graduation at the
high end of the gauge scale, making them clearly vis-
ible within the instrument cluster in daylight. When
illuminated from behind by the panel lamps dimmer
controlled cluster illumination lighting with the exte-
rior lamps turned On, the white graphics appear
white, the blue graphics appear blue, and the red
graphics appear red. The orange gauge needle is
internally illuminated. Gauge illumination is pro-
vided by replaceable incandescent bulb and bulb
Fig. 11 Cruise Indicator
Fig. 12 Engine Coolant Temperature Icon
TJ
INSTRUMENT CLUSTER
8J - 25