equipped, the ambien t temper ature indication can be
toggled with th e clock indica tion on the right side of
the mult i-fun ction indica tor Liquid Crystal Displa y
(LCD) loca ted nea r th e lower edge of t he instrument
cluster, direct ly below the speedomet er. The a mbient
temper ature in dication consist s of a numer ic value
with a “+” (plus) or “"” (min us) prefix, and the unit
of measure is iden tified wit h th e char acter s “°C”
(Cana dian veh icles only) or “°F ” (Unit ed Sta tes vehi-
cles only) located directly above t he tempera ture
indication. The indica tions of the ambient tempera -
ture indicator are not visible when th e LCD is not
illuminated. When illuminat ed th e indications
appear as dar k cha racter s and icons silhouetted
aga inst a n amber field. When t he exterior lighting is
turned Off, the display is illuminat ed a t m aximum
brightness. When th e exterior lighting i s tur ned On
the displa y illuminat ion level can be adjusted in con-
cert with the cluster gen eral illu mination lighting
using th e “+” (plus) and “"” (minus) multi-fu nction
indicator push bu ttons. The ambient tem perature
indicator is serviced as a unit with th e instru ment
cluster.
OPERATION
The optional am bient tempera ture indicator gives
an indication to the vehicle oper ator of the outside
air temper atur e. Th is indicator is controlled by the
instr umen t cluster microprocessor ba sed u pon cluster
pr ogrammin g and a ha rd wir ed input received by the
cluster from the ambient tem perat ure sensor. The
ambient temperatur e indicator is completely con-
trolled by the in strument cluster logic circu it, and
that logic will allow t his indicator to operate when-
ever the multi-function in dicator Liqu id Cr ystal Dis-
play (LCD) is act ivated. Th erefore, t he ambient
temper ature indicator remains functional regardless
of the ign ition switch position .
The veh icle opera tor can choose to have t he ambi-
ent tempera ture indicator displayed inst ead of the
clock information , but the clock and ambient temper-
ature indica tor ca nnot be displayed at th e sam e time.
The clock or am bient temper ature in dicator display
opt ion is selected using t he multi-function indicator
clock swit ch on the in st rumen t cluster circu it board.
This switch is actu ated m anua lly by depressing the
clock switch push bu tton that extends through th e
lower edge of the cluster lens below the left end of
the multi-function indicator. Actua tin g this switch
momen tarily will toggle the display bet ween the
clock and ambient temper atu re indicator modes.
Actuating th is switch twice within about one second
will cause the display to toggle, but then au tomat i-
cally revert to the originally selected mode aft er
about t wenty seconds.
The ambient tempera ture sensor locat ed below t he
front bumper is a Negative Temper ature Coefficient
(NTC) thermistor. The interna l resistan ce of th e sen-
sor is redu ced as the am bient tempera ture rises. The
instr umen t cluster contin ually monitors the r esis-
tance t hrough the sensor to determ ine the tem pera-
ture value t o be displayed. The cu rren t valu e is
displayed immediately aft er the LCD is activat ed.
The displa y value will r emain sta tic regar dless of
decreases in th e sen sor resistan ce (temperatur e r is-
ing) below vehicle speeds of 10 to 15 kilomet ers-per-
hour (6 t o 9 miles-per-hour). Decrea ses in the sensor
resistance a bove 15 kilometers-per-h our (9 miles-per-
hour) and increa ses th e sen sor resistance (tempera-
ture fallin g) regar dless of veh icle speed ar e displa yed
su bject to a sixty second dela y.
The am bient tempera tur e sen sor is con nected to
the instr umen t clu ster in series between t he ambien t
temper ature sensor retur n and sense circuits. The
ambient temper atur e sensor and the ret urn and
sense circuits to the instr umen t cluster can be diag-
nosed u sing convent ional diagnostic tools an d met h-
ods. For proper diagn osis of the instr umen t cluster
circuitry t hat controls th e ambien t tem perat ure indi-
cator, a diagnostic scan tool is requir ed. Refer to the
appropriate diagnostic in formation.
BRAK E I N DI CAT OR
DESCRIPTION
A brake indicator is standard equipm ent on all
instr umen t clust ers. Th e brake indica tor is located
near the lower edge of th e instrument cluster, to the
left of the mu lti-function indicator display. In vehi-
cles built for the United Sta tes mar ket , the bra ke
indicator con sists of a st encil-like cutout of the word
“BRAKE ” in the opaque layer of the in st rument clus-
ter overlay. In vehicles built for the Canadia n ma r-
ket , the bra ke indicator consists of the Inter national
Contr ol and Display Symbol icon for “Brake Fa ilu re”
imprinted within a r ectan gular cut out in the opa que
layer of the instr umen t clust er over lay. In eit her
case, th e dark out er la yer of the overla y prevent s t he
indicator from being clear ly visible when it is not
illuminated. A red Light Emitting Diode (LE D)
behind th e cut out in the opa que layer of the overlay
causes th e “BRAKE” text to appea r in red, or the
icon to appear silhouetted a gainst a red field throu gh
the tran slucen t outer layer of the overlay when t he
indicator is illu min ated from behind by the LED,
which is solder ed onto the instrumen t cluster elec-
tronic cir cuit board. The bra ke in dicator is serviced
as a unit wit h the instr umen t cluster.
OPERATION
The bra ke in dicator gives an indica tion to the vehi-
cle operator wh en t here are certa in brake hydr aulic
system ma lfun ctions as indica ted by a low br ake
hydra ulic fluid level condition, or when ther e is a
pr oblem in the electron ic br ake force distribut ion
8J - 12 INSTRUMENT CLUSTER VA
To Next Page
Loading...
