secured t o t he floor under the Dr iver seat an d
receives power fr om th e Fuse Block No. 1. Wh en -
ever t h e ign it ion key is t ur n ed to th e r u n or st ar t
posit ion, th e ACM per for m s a system test. The ACM
can n ot be r epa ir ed or adju sted.
The m icropr ocessor in t h e ACM m on itor s t h e
in t erna l a n d extern a l a irbag system electrica l cir-
cuit s t o determin e t h e system r eadin ess. Wh en a
mon itor ed syst em is det er m in e t o be out of r a nge,
th e ACM will set bot h a ct ive a n d st or ed dia gn ostic
tr ou ble codes (DTC). The ACM also con t a in s an
ener gy-st or a ge ca pa cit or. This ca pacit or st ores
enou gh electr ical en ergy t o deploy t h e fr on t a ir ba g
compon en t s for t wo seconds followin g a ba t t er y
discon n ect or failu r e durin g an impact .
The Acceler om et er in th e ACM is u sed to sense
th e r at e of vehicle decelerat ion, provide verifica t ion
of t h e dir ection a n d sever it y of a n impa ct . Wh en th e
pr eprogr am m ed condit ions a r e met, the ACM sends
an electr ical sign al t o deploy th e a ppr opr ia te fron t
air bag syst em com pon ent s a nd a deployment n ot i-
fica t ion .
To provide a n a ccident r esponse n ot ifica t ion, the
ACM is h ar dwir ed t o t h e Cent r a l Timer modu le
(CTM) a n d E ngine Con t r ol Module (E CM). Wh en a
deploym en t occu rs t h e ACM provides a 50ms 10.0
volt pu lse to t h e CTM a nd E CM. When t h e Acciden t
Repor t n ot ifica t ion sign a l is r eceived t he CTM un-
locks th e door lock s a n d t h e E CM st a lls t he en gin e.
The Acciden t sign a l will set a DTC in t h e CTM a n d
th e door locks will n ot work un t il the DTC h a s been
era sed. The E CM will set a DTC if th e Accident
Repor t circuit is short ed to bat t er y volta ge. The
ACM saves th e deployment r ecor d a nd a ft er t h r ee
deploym en t s th e ACM must be repla ced. The
DRBIII"can be u sed to test t h e Accident Repor t
Not ifica t ion fea t ur e: select t h e SYSTE M TEST from
th e ACM m a in m en u . Then select the An alog Cr a sh
Output System Test.
The ACM is h a r dwir ed to th e Inst r u m en t Clu st er
(MIC) t o con t r ol Wa r n in g Indica t or (SRS indicator ).
Wh en DTCs becomes act ivate, th e ACM illumin at es
th e War n ing In dica tor by pulling t h e indicator
cir cu it low. The SRS in dica t or is th e only poin t a t
which the cust om er ca n observe sym pt om s of a
syst em m a lfu n ct ion .
As pa r t of t he system t est t h e ACM illu m in a t es
th e War n in g Indica t or on for 4.0 secon d bu lb test .
After t he la mp check, if th e in dica tor tu r ns off, it
mean s t h a t t h e ACM ha s ch ecked t h e syst em a n d
foun d it t o be free of discernible m a lfu nct ions.
NON-CRITICAL DTCs
If t h e la mp com es on a n d st a ys on for a per iod
lon ger t h a n 4.0 seconds (about 10.0 secon ds) is
usu a lly a stor ed DTC (in term it t ent pr oblem) in t h e
system.
CRITICAL DTCs
DTCs th a t cou ld lea d t o a con dit ion wh er e the
sa fety devises ma y n ot deploy or incorr ectly deploy.
In t h e even t of su ch a DTC, th e sa fety of t h e vehicle
occupa n t s ca n n o lon ger be gu a r a n t eed. If t h e lamp
rema in s on , th ere cou ld be a n act ive DTC in t h e
syst em . Som e DTCs, In tern a l Modu le a n d squib
DTCs, will keep t h e in dicat or illumin at ed even if
th e codes a r e n o longer a ct ive.
ACM NOT CONFIGURED FOR PASSENGER
AIRBAG AND TENSIONER
If a ft er repla cing t h e ACM t h e Air ba g Wa r n in g
In dica t or flash es cont in u ou sly t h e ACM m u st be
configur ed for t h e P a ssenger Air ba g an d Ten sioner.
Select Miscella n eous fr om t h e ACM m a in menu a n d
configur e t h e P a ssen ger Air bag Ten sion er squibs.
WARNING:
THE AIRBAG SYSTEM IS A
SENSITIVE, COMPLEX ELECTROMECHANICAL
UNIT. BEFORE ATTEMPTING TO DIAGNOSE OR
SERVICE ANY AIRBAG SYSTEM OR RELATED
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENTS YOU MUST
FIRST DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE. WAIT
TWO MINUTES FOR THE SYSTEM CAPACITOR
TO DISCHARGE BEFORE FURTHER SYSTEM
SERVICE. THIS IS THE ONLY SURE WAY TO
DISABLE THE AIRBAG SYSTEM. FAILURE TO
DO THIS COULD RESULT IN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, NEVER STRIKE OR KICK THE
AIRBAG CONTROL MODULE, AS IT CAN
DAMAGE THE IMPACT SENSOR OR AFFECT
ITS CALIBRATION.
WARNING: IF AN AIRBAG CONTROL
MODULE IS ACCIDENTALLY DROPPED
DURING SERVICE, THE MODULE MUST BE
SCRAPPED AND REPLACED WITH A NEW
UNIT. FAILURE TO TAKE THE PROPER
PRECAUTIONS COULD RESULT IN
ACCIDENTAL AIRBAG DEPLOYMENT AND
PERSONAL INJURY OR DEATH.
3.1.1 DRIVER AIRBAG
The a ir bag pr ot ective tr im cover is th e m ost
visible part of t he dr iver side a irbag syst em. The
air bag is m oun t ed dir ectly t o t h e st eerin g wheel.
Locat ed u n der t h e t r im cover a r e th e a ir ba g cush ion
an d t h e a ir ba g cu sh ion suppor t in g com pon ent s.
2
GENERAL INFORMATION
