Dodge 2006 Sprinter, Manual

Page: 318 / 2315

en a ble t h e H CU t o per for m t h e br a ke flu id m a n a ge-
m en t con t r ol a s t h e com bin a t ion /pr opor t ion in g
va lves.
Th e Bosch 5.7 syst em u ses t h e CAB/H CU/P u m p
Mot or t o m a ke a n in t egr a l elect r on ic/h ydr a u lic u n it
wh ich sh a r es da t a wit h ot h er elect r on ic m odu les on
t h e veh icle via t h e CAN C Bu s n et wor k. To a ccess
DTCs fr om t h e CAB, t h e DRBIII
" u ses t h e K-ABS
lin e loca t ed in t h e Da t a Lin k Con n ect or (DLC).
3.3 BRAKE ASSIST SYSTEM (HBA)
Th e Br a ke Assist Syst em (H BA) a n a lyzes h ow
h a r d a n d fa st t h e dr iver wa n t s t o br a ke. It m on it or s
t h e br a ke pr essu r e via a pr essu r e sen sor. Th e
pa ssen ger ca r br a ke a ssist syst em u ses a va cu u m
boost er solen oid. Th e Spr in t er u ses t h e h ydr a u lic
con t r ol u n it t o develop t h e br a ke pr essu r e.
3.4 TCS (ASR)
Th e pr im a r y fu n ct ion of t h e Tr a ct ion Con t r ol Syst em
is t o r edu ce wh eel slip a n d m a in t a in t r a ct ion a t t h e
dr iven wh eels wh en t h e r oa d su r fa ces a r e slipper y. Th e
Tr a ct ion Con t r ol Syst em r edu ces wh eel slip by a pplyin g
t h e br a ke t h a t h a s lost t r a ct ion . Th e syst em is design ed
t o oper a t e a t speeds below 50 km /h (30 m ph ). Th e
en gin e’s t or qu e ca n be r edu ced by t h e E CM via t h e CAN
C Bu s, if n ecessa r y. Th e TCS ca n be dea ct iva t ed wit h
swit ch on t h e da sh . Th e Tr a ct ion Con t r ol Syst em u ses
t h e ABS t o in dica t e spin n in g t ir es t o en a ble t h e t r a ct ion
con t r ol fu n ct ion . Th e TCS soft wa r e is in t h e CAB.
Th e TCS (ASR) per for m s t h e followin g fu n ct ion s:
1. E n gin e power der a t e
2. E n gin e deceler a t ion r egu la t ion . If t h e veh icle is
on a pa t ch of ice, t h e sim ple a ct ion of r elea sin g
t h e t h r ot t le is en ou gh t o ca u se t h e r ea r wh eels t o
slip. To a void t h is, t h e t h r ot t le in pu t is r egu la t ed
so power dr ops slowly in st ea d of a br u pt ly. Th e
en gin e power is r edu ced (deceler a t ed) a s n eces-
sa r y.
3.5 ELECTRONIC BRAKE DISTRIBUTION
(EBD)
Th e syst em wa s en h a n ced a n d elim in a t es t h e
n eed for t h e ALB syst em (loa d sen sin g va lve). All
E SP equ ipped m odels will n ot h a ve ALB. Th e E BV
syst em self-a da pt s t o oper a t in g con dit ion s. It de-
t ect s t h e veh icle’s pa yloa d wh en t h e veh icle st a r t s
a n d pu lls a wa y. Ba sed on t h e a cceler a t ion r a t e
wh en t h e veh icle fir st pu lls a wa y fr om a st a n dst ill,
t h e syst em is a ble t o ca lcu la t e t h e a ct u a l pa yloa d.
Th is is a r ou gh est im a t e wh ich is u sed in it ia lly.
La t er on , t h e syst em ga t h er s m or e pr ecise in for m a -
t ion by m on it or in g t h e br a ke pr essu r e a n d wh eel
speed a n d n ega t ive slip wh en t h e dr iver a pplies t h e
br a kes. Th e syst em will t h en pr odu ce a m or e a ccu -
r a t e ca lcu la t ion of pa yloa d depen din g on br a ke
r et a r da t ion . Th e a da pt a t ion is er a sed wh en t h e
ign it ion is swit ch ed off. A n ew a da pt a t ion will occu r
on t h e n ext dr ivin g cycle. By defa u lt , t h e syst em
a ct s u pon t h e veh icle a s if in a n u n loa ded con dit ion
(sa fe m ode).
On ce a n ew dr ivin g cycle begin s wit h t h e veh icle
in a fu lly loa ded con dit ion (wit h ou t h a vin g ga t h er ed
m or e pr ecise in for m a t ion ) t h e syst em will det ect
ABS a ct u a t ion in t h e fr on t wh eels a n d will a llow
en ou gh pr essu r e t o be a pplied t o t h e r ea r a xle, t o a n
ext en t wh er e t h e wh eels a r e ju st a bou t t o lock u p
(m a xim u m br a kin g possible).
Th e syst em ca lcu la t es t h e br a kin g for ce a t t h e
fr on t a n d r ea r a xles. If t h e dr iver a pplies t h e br a kes
gen t ly a n d t h en r ea lizes h e n eeds t o a pply t h e
br a kes fu r t h er, t h e E BV a llows t h e pr oper pr essu r e
t o be a pplied t o t h e fr on t a n d r ea r br a kes.
Th e E BV a lso con t a in s a fea t u r e ca lled “cor n er
br a ke syst em ” (CBS) wh ich oper a t es wh en t h e ve-
h icle is br a ked wh ile cor n er in g t o a void a possible
over st eer in g con dit ion . Th e E BV m on it or s t h e
wh eel speed of bot h r ea r wh eels t o det ect wh en t h e
veh icle is cor n er in g a n d a llows pr ecise br a ke pr es-
su r e a pplica t ion t o t h e fr on t a n d r ea r br a kes. Also
wh en t h e br a kes a r e a pplied du r in g cor n er in g, t h e
ou t er wh eels get m or e of t h e veh icle’s weigh t wh ile
t h e in n er wh eels get less weigh t a n d cou ld lose
t r a ct ion (wh eel lock u p). Th e E BV syst em split s t h e
pr essu r e bet ween left a n d r igh t sides in a ddit ion t o
fr on t a n d r ea r br a kes.
3.6 VEHICLE CONTROLLING (FZR)
Ve h ic le c o n tro llin g (F ZR) r equ ir es a ddit ion a l
sen sor s t o oper a t e. Th e t er m E SP r efer s t o t h e
soft wa r e of t h e syst em . Th e t er m F ZR r efer s t o t h e
syst em con t r oller. Th e TCS (ASR) syst em r equ ir es
wh eel speed sen sor s t o m on it or wh eel slip a n d CAN
bu s com m u n ica t ion s t o r egu la t e en gin e power. In
a ddit ion t o t h ese in pu t s, t h e veh icle con t r ollin g
(F ZR) r equ ir es a st eer in g a n gle sen sor, a n d a la t er a l
a cceler a t ion /ya w r a t e sen sor.
Th e E SP syst em does n ot t a ke t h e veh icle loa d
in t o a ccou n t . In st ea d, t h e coefficien t of fr ict ion is
ca lcu la t ed in a 20 m illisecon d per iod, wh er e t h e
con t r oller m ea su r es t h e r a t e a t wh ich t h e wh eel
speed is deceler a t ed, a s br a ke pr essu r e is a pplied t o
t h e wh eel.
3.7 SYSTEM COMPONENTS
•
Con t r oller An t ilock Br a ke (CAB)
•
H ydr a u lic Con t r ol Un it (H CU)
•
P u m p Mot or
2
GEN ERAL I N FORM AT I ON