Mitsubishi 3000GT 1991 Service Manual page 760

SERVICE BRAKES -
E-l When the following diagnosis codes are displayed "11 FR SNSR. OPEN"
"12 FL SNSR. OPEN" "13 RR SNSR. OPEN" "14 RL SNSR. OPEN"
[Explanation]
The ABS ECU detects breaks in the wheel speed
sensor wire. This trouble code is
speed sensor signal is not input (or short circuited)
or if its output is low when starting to drive or while
driving.
E-2 When diagnosis code "15 VEH. SPD. SNSR." is displayed
[Explanation]
This trouble code is output when there is an
abnormality (other than broken wire or short circuit)
in any of the wheel speed sensor output signals
while driving.
[Hint]
The following can be considered as the cause of the
wheel speed sensor output abnormality.
Distortion of rotor, teeth missing
l
Low frequency noise interference when sensor
l
harness wire is broken
Noise interference in sensor signal
l
Sensor output signal is below the standard value
l
or amplitude modulation is over the standard
value. Using an oscilloscope to measure the
wave shape of the wheel speed sensor output
signal is very effective.
[Hint]
In addition to a broken wire/short circuit in the wheel
speed sensor, also check whether the sensor gap is
if the wheel
too large, sensor harness wire is broken, or sensor
harness and body connector are not properly con-
l
l
NOTE
(2) Except for the case where a fault condition
SPEED SENSOR
TSB Revision
Broken sensor harness
Poor connection of connector
bending and lightly stretching it.
exists in the system, but the inspection results
are normal; if an abnormality cannot be found in
the sensor. circuit displayed as abnormal, erase
the diagnosis code and turn the ignition switch
to OFF once, and then test-drive again.
If the same trouble code is output, replace the
ABS ECU. If the trouble does not occur any-
more, the problem is likely to be with the ABS
- - -.
(If the trouble is in the speed sensor circuit, but
is difficult to recreate, it will recur even after the
ABS ECU has been replaced.)
8 8