Mitsubishi 3000GT Service Manual page 847

SERVICE BRAKES - Anti-lock Braking System Troubleshooting
When the following diagnostic trouble codes are displayed "11 FL SNSR. OPEN" "12 FR SNSR.
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OPEN" "13 RL SNSR. OPEN" "14 RR SNSR. OPEN"
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[Explanation]
The ABS ECU detects breaks in the wheel speed
sensor wire. This trouble code is output if the wheel
speed sensor signal is not input (or short circuited)
or if its output is low when starting to drive or while
driving.
When diagnostic trouble code "15 VEH. SPD. SNSR." is displayed
[Explanation]
This trouble code is output when there is an ab-
normality (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
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Low frequency noise interference when sensor
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harness wire is broken
Noise interference in sensor signal
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Sensor output signal is below the standard val-
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ue 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.
Broken sensor harness
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[Hint]
In addition to a broken wire/short circuit in the wheel
speed sensor, also check whether the sensor gap
is too large, sensor harness wire is broken, or sensor
harness and body connector are not properly con-
NOTE
(1) If contact is poor, check the sensor cable by
bending and lightly stretching it.
(2) Except for the case where a fault condition
exists in the system, but the inspection results
are normal; if an abnormality cannot be found
erase the diagnostic trouble code and turn the
ignition switch to OFF once, and then test-drive*
again.
occur anymore, the problem is likely to be with
the ABS ECU.
but is difficult to recreate, it will recur even after
the ABS ECU has been replaced.)
(3) *: Drive at 19 mph or higher for more than
TSB Revision
in the sensor circuit displayed as abnormal,
If the same diagnostic trouble code is output,
replace the ABS ECU. If the trouble does not
(If the trouble is in the speed sensor circuit,
30 seconds.
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