The CAB continua lly mon itors t he E SP circuits
and sensor s to decide whether the syst em is in good
operat ing con dition. The CAB then sends t he proper
lam p-on or lamp-off messages to the instrument clus-
ter. If the CAB sends a l a mp-on m essa ge after the
bulb test, it indicates tha t the CAB ha s det ected a
system ma lfunction and/or th at the ESP system ha s
become inopera tive. The CAB will store a Diagn ost ic
Trouble Code (DTC) for an y malfunct ion it detects.
For proper diagnosis of the E SP system, the CAB,
the CAN dat a bu s, th e electr onic m essa ge input s to
the instrument cluster, or th e instrument cluster cir-
cuitry th at controls t he ESP indicator, a diagn ost ic
sca n tool is required. Refer to t he appropriate diag-
nostic infor mation.
FU EL FI LT ER CLOGGED I N DI -
CAT OR
DESCRIPTION
A fuel filter clogged indicator is sta ndard equip-
ment on a ll inst rumen t clust ers. Th e fuel filter
clogged indicator is located near the left edge of th e
instr umen t clu st er, next to th e t achom eter. The fuel
filt er clogged indica tor consists of the Interna tional
Contr ol and Display Sym bol icon for “F uel F ilter ”
imprinted within a r ectan gular cut out in the opa que
layer of the instrument cluster overlay. The dar k
outer layer of the overlay pr events t he in dicator fr om
being clear ly visible when it is not illu minated. An
amber Ligh t E mit ting Diode (LED) behind the cut out
in the opa que la yer of the overlay ca uses the icon to
appear silhouet ted aga inst an amber field through
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 circu it board. Th e fuel filter clogged indica tor
is serviced as a unit with the instrument cluster.
OPERATION
The fuel filt er clogged indicator gives a n indication
to th e vehicle oper ator when the pressu re in the fuel
system is low, which could indica te th at th e fu el filter
is clogged. This indicator is controlled by a tra nsistor
on the instr umen t cluster circu it board based upon
cluster pr ogrammin g a nd elect ronic messages
received by the clu st er from the Engine Con trol Mod-
ule (ECM) over the Controller Area Network (CAN)
da ta bus. The fuel filter clogged indicator Light Emit-
ting Diode (LED) is complet ely controlled by th e
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 i n st rumen t clust er will turn on the fuel filter
clogged indicator for the followin g rea son s:
• Bulb Test - Ea ch time the ignition switch is
turned to the On position t he fuel filter clogged indi-
cator is illuminat ed by the clu st er for abou t t wo sec-
onds as a bulb test .
• Fu e l F ilt e r Clo gg e d La m p -On Me ss a g e -
Each time the cluster receives a la mp-on message
from the ECM, th e fuel filter clogged indicator will
be illu minated. The indicator remains illu min ated
until th e cluster receives a lamp-off message from
the ECM, or unt il the ignition swit ch is tu rned to th e
Off position, whichever occur s first.
The ECM con tin ually monit ors the low fuel pres-
su re sensor located at t he inlet of the high pressure
fuel pump to decide wh ether the fuel system is in
good operat ing condition. Th e ECM then sends th e
pr oper lamp-on or lamp-off messa ges t o the instru-
ment clu st er. If the ECM sen ds a lamp-on message
after t he bulb test , it in dicates th at the ECM has
detected a low pressure condition in the fuel system,
which could result from a clogged fuel filter or from
any ot her restriction s in t he fuel delivery system.
The E CM will store a Diagnostic Trouble Code (DTC)
for any malfu nction it detects. For pr oper diagnosis
of t he low fu el pr essu re sen sor, the ECM, the CAN
da ta bus, the electron ic message input s to th e instr u-
ment cluster, or t he in st rumen t cluster circuitry that
controls th e fuel filter clogged indicator, a diagnostic
sca n tool is required. Refer to t he appropriate diag-
nostic infor mation.
FU EL GAU GE
DESCRIPTION
A fuel ga uge is st andar d equipment on all in stru-
ment clust ers. The fuel ga uge is located in t he lower
right cor ner of the inst rument cluster, t o t he right of
the speedom eter. The fu el gauge consist s of a m ov-
able gau ge needle or point er controlled by the instr u-
ment cluster circuitry a nd a fixed 45 degree scale on
the cluster overlay th at reads left-to-r igh t from “F”
(or Full) to “E” (or Empt y). An Int erna tional Con trol
and Display Sym bol icon for “Fuel” is located on th e
cluster overla y, direct ly to the left of the low end of
the sca le.
The fuel gauge graphics are whit e a gainst a black
field, making them clearly visible within the in st ru-
ment cluster in daylight . When illuminat ed from
behind by the panel lamps dimmer controlled cluster
illumination lighting with th e ext erior lamps turned
On, th e white graphics appear a mber. The orange
gauge ne ed le is internally illuminated . Gauge illumi-
nation is provided by Light Em itting Diode (LE D)
units solder ed onto the in strument cluster electr onic
VA INSTRUMENT CLUSTER 8J - 17
To Next Page
Loading...
