or until t he ignition switch is turned t o the Off posi-
tion, which ever occurs first.
A bra ke wear sen sor locat ed at ea ch wheel provides
a hard wired gr ound in pu t to the instr umen t cluster
circuitry t hrough the brake wear sense circu it when-
ever the brake linings for that wheel have exceeded
their wear limit s. The four nor mally open brake wear
sensors ar e con nected in parallel between ground and
instr umen t cluster. The br ake wear sensor s an d th eir
input circuit t o the instrument clu st er ca n be dia g-
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 the brake wear indicator, a
diagnostic scan tool is required. Refer to the appro-
pr iate diagnostic in formation.
CH ARGI N G I N DI CAT OR
DESCRIPTION
A cha rging indicator is st andar d equipm ent on all
instr umen t clu st ers. The chargin g in dicator is located
near the lower edge of th e instrument cluster, to the
left of the m ult i-function indicator displa y. The
charging in dicator consist s of t he Inter nat ional Con-
trol and Display Sym bol icon for “Ba tter y Char gin g
Condition” imprinted within a rect angula r cu tout in
the opa que layer of the instr umen t cluster overlay.
The da rk outer la yer of th e overla y prevent s the indi-
cator from being clea rly visible when it is not illumi-
nated. A red Light Emitting Diode (LED) behind th e
cutout in the opa que la yer of the overla y causes 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 circuit board. The char gin g in dicator is ser-
viced a s a unit with t he in st rumen t cluster.
OPERATION
The char gin g indicator gives a n indica tion to the
vehicle oper ator when th e elect rica l system volta ge is
too low. This indica tor is con trolled by a tr ansist or on
the instr umen t cluster circuit board based u pon clus-
ter progr amm ing and a ha rd wired input from the
generat or. The cha rging indicator Light E mit ting
Diode (LED) is completely controlled by the instr u-
ment cluster logic circuit, an d t hat logic will only
allow this indicator to opera te when the inst rument
cluster detect s tha t th e ign ition swit ch is in t he On
position . Ther efore, the LED will alwa ys be off wh en
the ignition swit ch is in any position except On . The
LED only illu min ates when it is pr ovided a path t o
ground by the instru ment cluster transistor. Th e
instr umen t clu st er will turn on the chargin g indica-
tor for the following rea son s:
• Bulb Test - Ea ch time the ignition switch is
turned to t he On position with the engine not run-
ning the cha rging indicator is illumina ted by the
instr umen t cluster as a bulb test .
• Ge nera t o r Inp ut - E ach time t he cluster
detects tha t the voltage of the gener ator in pu t is 12.7
volt s or lower while the engine is running, t he cha rg-
ing in dicator will be illuminat ed. The indica tor
rema ins illuminated until the cluster detect s th at t he
volt age of the gener ator input is above 12.7 volts, or
until the ignition switch is t urned t o t he Off position,
which ever occurs first.
The generator provides a h ard wir ed input to the
instr umen t clust er circuitr y on t he engine ru nning
(D+) cir cuit. If the inst rument clu st er turns on the
indicator while the en gine i s run ning, it may indica te
that the char ging syst em requires service. The gener-
ator input circu it to th e instru ment clust er can be
diagnosed using convent iona l diagn ost ic tools an d
meth ods. For proper diagnosis of the cha rging sys-
tem, or the instru ment cluster circuitry th at cont rols
the ch arging indicator, a diagnostic sca n t ool is
required. Refer to the appropriate diagn ost ic infor-
mation.
CLOCK
DESCRIPTION
An electr onic digital clock is standar d equipmen t
on all instr umen t cluster s. In vehicles equipped with
the opt ional ambient tem per ature in dicator, th e clock
indication can be toggled with th e am bient temper a-
ture indication on th e right side of the m ulti-funct ion
indicator Liquid Cr ystal Displa y (LCD) loca ted near
the lower edge of the instr umen t cluster, dir ectly
below the speedom eter. The clock provides a 12 hour-
based, digital indication of the curr ent hours and
minutes. The indications of the clock a re not visible
when the LCD is not illuminat ed. When illuminat ed
the indications appear as dar k ch aracters silhouet ted
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. Th e clock is serviced as a
unit with t he in st rumen t cluster.
OPERATION
The clock gives a n in dication to the vehicle opera-
tor of t he curren t time. The elect ronic digital clock is
controlled by the instrumen t cluster microprocessor
based upon cluster progr amming. The clock display is
complet ely controlled by th e instrument cluster logic
circuit, and that logic will only allow this indica tion
to be viewed wh en the multi-fu nction indicator Liq-
uid Cryst al Displa y (LCD) is act iva ted. However, the
8J - 14 INSTRUMENT CLUSTER VA
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