7 SPN, SID, FMI Fault Codes
77
WABCO Maintenance Manual MM-0112 (Revised 07-18)
Figure 7.11
Figure 7.11
SPN SID FMI
Blink
Code
Description
Warning
Light
System
Reaction
Cause Action
Right Third Axle Wheel Speed Sensor
794 6 1 3 + 5 Air Gap ABS WL
ABS Wheel
Disabled
ESC/RSC/ATC/
HSA Disabled
Sensor air gap is too
large, sensor output
voltage is too low
but is high enough to
be read by ECU.
• Adjust wheel sensor to touch tone ring.
• Check condition of ABS sensor head.
• Check for loose wheel bearings or excessive hub runout.
• Check mounting of ABS tone ring and condition of teeth.
• Check condition and retention of ABS sensor spring clip.
• Check ABS sensor cable routing and clipping.
• Turn the wheel at half a revolution per second and verify 0.2 AC volt sensor output
voltage.
794 6 2 5 + 5 Incorrect Tire ABS WL
ABS Wheel
Disabled
ESC/RSC/ATC/
HSA Disabled
System has
detected a
significant difference
in the proportion of
tire diameter to
number of tone ring
teeth between wheel
ends. 10% (+/-2%)
• Check for tire size mismatch.
• Check for correct number of tone ring teeth.
• Verify that ECU is programmed for the correct vehicle.
• Contact WABCO or OEM.
794 6 3 4 + 5
Shorted to
UBATT
ABS WL
ABS Wheel
Disabled
ESC/RSC/ATC/
HSA Disabled
Continuity between
the sensor
connection and
battery voltage
(short circuit) is
detected.
• Verify 900-2000 ohms resistance through sensor circuit.
• Verify no DC voltage through sensor circuit Key ON.
• Check for corroded or damaged wiring between the ECU and the ABS wheel speed
sensor.
794 6 4 4 + 5
Shorted to
Ground
ABS WL
ABS Wheel
Disabled
ESC/RSC/ATC/
HSA Disabled
Continuity between
the sensor
connection and
ground (short circuit)
is detected.
• Verify 900-2000 ohms resistance through sensor circuit.
• Check for continuity between the ABS sensor connection and ground.
• Check for corroded or damaged wiring between the ECU and the ABS wheel speed
sensor.
• Verify wheel speed sensor wires are not switched left/right.
794 6 5 4 + 5 Open Circuit ABS WL
ABS Wheel
Disabled
ESC/RSC/ATC/
HSA Disabled
An open circuit has
been detected, i.e.
ECU detects a
disconnected wheel
speed sensor.
• Check sensor, sensor cable and connectors to verify no loose or damaged connection.
• Verify 900-2000 ohms resistance through sensor circuit.
• Verify wheel speed sensor wires are not switched left/right.
794 6 6 4 + 5 Short Circuit ABS WL
ABS Wheel
Disabled
ESC/RSC/ATC/
HSA Disabled
Continuity
interruption between
the sensor
connections (short
circuit) has been
detected.
• Verify 900-2000 ohms resistance through sensor circuit.
• Check for corroded or damaged wiring between the ECU and the ABS wheel speed
sensor.
4010654a
To Next Page
Loading...
