7
SPN, SID, FMI Fault Codes
74
WABCO
Maintenance Manual MM-0112 (Revised 07-18)
Figure 7.8
Figure 7.8
SPN
SID
FMI
Blink
Code
Description
W
arning
Light
System
Reaction
Cause
Action
792
4
7
6 + 3
Incorrect T
one
Ring
ABS WL
ABS Wheel
Disab
led
ESC/RSC/A
TC/
HSA Disab
led
Wheel speed signal
drops out
per
iodically at
speeds higher than
6 mph.
•
Chec
k f
o
r damaged or missing teeth on tone r
ing.
•
V
e
ri
fy tone r
ing is not corroded or with contamination.
792
4
8
3 + 3
Excessiv
e
Slip
ABS
WL
ABS Wheel
Disab
led
ESC/RSC/A
TC/
HSA Disab
led
Wheel slip o
v
er 16
seconds
contin
uously has
been detected.
•
Adjust wheel sensor to touch tooth wheel.
•
Chec
k sensor gap
.
•
Chec
k f
o
r loose wheel bear
ings or e
xcessiv
e
hub r
u
nout.
792
4
9
5 + 3
Wires
Mismatched
ABS WL
ABS Wheel
Disab
led
ESC/RSC/A
TC/
HSA Disab
led
A sensor lead from
an incorrect wheel
end has been
detected.
•
Chec
k f
o
r mismatch f
a
ult of another sensor
.
•
V
e
ri
fy correct har
ness location and wir
ing f
o
r sensor
.
•
Chec
k f
o
r corroded or damaged wir
ing betw
een the ECU and the ABS wheel speed
sensor
.
792
4
1
0
3
+ 3
Speed
Drop-Out
ABS WL
ABS Wheel
Disab
led
ESC/RSC/A
TC/
HSA Disab
led
A tempor
ar
y loss of
the ABS wheel
speed signal has
been detected.
•
Adjust wheel speed sensor until it touches the tone r
ing.
•
Chec
k f
o
r loose wheel bear
ings or e
xcessiv
e hub r
unout.
•
Chec
k sensor wir
ing and connectors f
o
r inter
m
ittent contact.
•
Chec
k condition of ABS sensor head.
•
Chec
k mounting of tone r
ing and condition of teeth.
•
Chec
k condition and retention of ABS sensor spr
ing clip
.
•
Chec
k ABS sensor cab
le routing and clipping.
•
Chec
k f
o
r corroded or damaged wir
ing betw
een the ECU and the ABS wheel speed
sensor
.
•
T
u
rn
the wheel at half a re
v
o
lution per second and v
e
ri
fy 0.2 A
C
v
o
lt sensor output
vo
lt
a
g
e
.
792
4
1
1
5
+ 3
Abnor
mal
Speed
(Chatter)
ABS WL
ABS Wheel
Disab
led
ESC/RSC/A
TC/
HSA Disab
led
Br
ak
e dr
ag or
chatter has been
detected.
Abnor
mal
vibr
ations detected
which aff
ect sensor
signal.
•
Chec
k f
o
r loose wheel bear
ings or e
xcessiv
e
hub r
unout.
•
Chec
k sensor wir
ing and connectors f
o
r inter
m
ittent contact.
•
Chec
k mounting of tone r
ing and condition of teeth.
•
Chec
k condition and retention of ABS sensor spr
ing clip as w
e
ll as the mounting b
loc
k.
•
Chec
k f
o
r corroded or damaged wir
ing betw
een the ECU and the ABS wheel speed
sensor
.
•
T
u
rn
the wheel at half a re
v
o
lution per second and v
e
ri
fy 0.2 A
C
v
o
lt sensor output
vo
lt
a
g
e
.
792
4
1
2
5
+ 3
F
requency
T
oo High
ABS WL
ABS Wheel
Disab
led
ESC/RSC/A
TC/
HSA Disab
led
A non-plausib
le
sensor frequency
has been measured.
•
Chec
k sensor wir
ing and connectors f
o
r inter
mittent contact.
•
Chec
k if br
ak
e at this location is oper
ating correctly
, i.e
., potentially dr
agging.
•
Chec
k f
o
r corroded or damaged wir
ing betw
een the ECU and the ABS wheel speed
sensor
.
4010651
a
