rema ins illuminat ed u ntil the cluster receives a
lam p-off message from the ECM, or u ntil th e ign ition
switch is tur ned to the Off posit ion, whichever occu rs
first.
The E CM cont inually mon itors t he constant engine
speed (ADR) swit ch a nd electr onic messages from the
Contr oller Antilock Brake (CAB) concer nin g t he sta -
tus of the four wheel speed sensors, th e pa rk brake
switch a nd the bra ke lamp switch t o det ermine t he
correct opera ting mode for th e ADR feat ure. Th e
ECM then sen ds the proper lamp-on or lamp-off mes-
sa ges to th e instrument cluster. See the own er’s man -
ual in the veh icle glove box for more in formation on
the featu res, use, activation an d dea ctivation of the
constan t engin e speed (ADR) fea ture. For proper
diagnosis of th e ADR fea tur e, th e ECM, t he CAB, t he
CAN dat a bu s, or th e elect ronic message inputs t o
the instr umen t cluster tha t control the ADR indica -
tor, a diagnostic sca n t ool is r equired. Refer to the
appropriate diagnostic in formation.
AI RBAG I N DI CAT OR
DESCRIPTION
An air bag indicator i s sta ndard equipmen t on all
instr umen t cluster s. The airbag indica tor is loca ted
near the left edge of th e instrument cluster, next to
the ta chomet er. The a irba g indicator consist s of a
st encil-like cutou t of the let ters “SRS” in th e opaqu e
layer of the instrument cluster overlay. The dar k
outer layer of the overlay pr events t he in dicator fr om
being cl early visible when it is not illuminat ed. A red
Light Emitting Diode (LED) behin d the cut out in the
opa que layer of the overla y ca uses t he “SRS” text to
appear in red through the tra nslucent outer la yer of
the overlay when the in dicator is illumina ted fr om
behind by t he LED, wh ich is soldered on to t he
instr umen t cluster electr onic circuit board. The air-
bag indicator is serviced as a un it with the instru-
ment cluster.
OPERATION
The airba g (SRS) indicator gives an indication to
the vehicle operat or when th e Airbag Control Modu le
(ACM) h as r ecorded a Diagn ost ic Trouble Code (DTC)
for a Supplemental Restraint System (SRS) circuit or
component malfunct ion. Such a DTC ma y in dicate
that the SRS is fau lty or inoper ative. The a irba g
indicator is controlled by a tra nsistor on th e i n st ru-
ment clust er circuit board based upon cluster pro-
gra mmin g and a har d wir ed in pu t received by th e
cluster fr om t he ACM. The airba g indicator Light
Emitting Diode (LE D) is complet ely cont rolled by t he
instr umen t cluster logic circu it, a nd th at logic will
only allow t his indicator to oper ate when th e instru-
ment cluster detect s th at the ignition switch is in t he
On posit ion. Therefore, the LED will a lways be off
when t he ignition switch is in an y position except
On. The LED on ly illuminates when it is provided a
pa th to grou nd by the instr umen t cluster tra nsistor.
The instr ument cluster will tur n on th e airbag in di-
cator for th e following rea son s:
• Bulb Test - Ea ch time the ignition switch is
turned to the On position t he airba g indicator is illu-
minated for about four seconds. The en tire four sec-
ond bulb test is a funct ion of th e ACM.
• Airba g La m p -On In p u t - Each time the cluster
receives a lamp-on in pu t from the ACM, the airbag
indicator will be illuminated. The in dicator can be
flashed on and off, or illum inated solid, as dictated
by th e ACM inpu t. For some DTC’s, if the problem
does not recur, the ACM will send a la mp-off input
automatically. Ot her DTC’s m ay requir e that a fault
be r epair ed and t he ACM be reset before a lam p-off
input will be sent. For more in format ion on the ACM
and th e DTC set and reset pa rameters, refer t o 8 -
ELECTRICAL/RESTRAINTS/AIRBAG CONTROL
MODULE - OP ERATION). The in dicator remains
illuminated until the cluster receives a lamp-off
input from the ACM, or until the ignition switch is
turned to t he Off position , whichever occurs first.
• Ai r bag I ndicator Mal f uncti on - Following the
seatbelt reminder funct ion, ea ch time the cluster
detects a malfunction in th e a irbag (SRS) indica tor or
the airbag indica tor circuit, the cluster will flash th e
seatbelt in dicator on a nd off. The cluster will con-
tinue to flash t he sea tbelt indicator u ntil t he a irba g
indicator circu it fa ult is resolved, or unt il t he ignition
switch is tur ned to the Off posit ion, whichever occu rs
first.
The ACM contin ually mon itor s the SRS cir cuit s
and sensor s to decide whether the syst em is in good
operat ing condition . The ACM then pr ovides the
pr oper lamp-on or lamp-off in pu ts t o t he instrument
cluster. If t he ACM pr ovides a lamp-on input aft er
the bulb test, it indicates tha t the ACM has detect ed
a system malfunction an d/or that t he a irba gs an d
seat belt tensioners ma y not deploy when required,
or may deploy when not required. Th e ACM will
st ore a DTC for any ma lfunction it det ects. The ACM
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 diagnosis of the SRS, th e ACM, or
the in strument clust er circuitry that controls the air-
bag indica tor, a dia gnostic scan t ool is requir ed. Refer
to th e appropriate diagnostic in formation.
AM BI EN T T EM PERAT U RE
INDICATOR
DESCRIPTION
An ambient tem perat ure indica tor is option al
equipm ent on a ll instrument clu st ers. In vehicles so
VA INSTRUMENT CLUSTER 8J - 11
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