MOTO GUZZI B043157 Service Station Manual page 118

Electrical system
5D90 electric malfunction: Electrical fault in sensor or cable harness.
Troubleshooting: Check the sensor connector and the ABS control unit connector. If they are not OK,
restore the connectors. If they are OK, check continuity of the white/brown cable between PIN 2 of the
sensor on the cable harness side and PIN 14 of the ABS control unit connector. If there is no continuity,
restore them. If there is, PIN 2 of the sensor on the cable harness side, with the sensor disconnected
and key set to ON, must have 12V voltage approximately: if there is no voltage, check PIN 2 for continuity
with the vehicle ground connection: if it is grounded, restore the cable harness. If OK, replace the control
unit. If PIN 2 has approx. 12 V, check the continuity of the white cable between PIN 1 of the sensor on
the cable harness side and PIN 13 of the ABS control unit connector. If there is no continuity, restore
the cable harness. If there is, replace the logic errors sensor.
P0501 Front wheel speed signal/sensor.
Connect to the ABS control unit diagnostics.
LOGIC ERRORS
Speed sensor
5D91 the signal works irregularly: faulty sensor or signal interference.
Troubleshooting: Check speed sensor retainer. If it is not OK, restore it. If it is OK, check if the tone
wheel is dirty, deformed or wrongly fixed. If any of this happens, replace the tone wheel. Otherwise,
replace the speed sensor.
5D92 the signal decreases periodically: Possible tone wheel fault due to deformations or dirt; pos-
sible alterations on the wheel bearing surface. In very rare cases, abnormal tone wheel vibrations.
Troubleshooting: Check if the tone wheel is dirty, deformed or wrongly fixed. If the tone wheel is not
OK, replace it. If it is OK, check for possible faults in the wheel bearings and if it is not OK, replace the
bearings.
5D93 missing signal or speed measured too low in relation to the rear wheel: faulty sensor or
missing sensor/tone wheel. Or excessive distance between the sensor and the tone wheel or tone wheel
with wrong number of teeth.
Troubleshooting: Check that the speed sensor and the tone wheel are installed. If they are not, install
them. If they are, check the speed sensor retainer. If it is not OK, restore it. If it is, check if the tone
wheel has the correct number of teeth or if it is dirty, deformed or wrongly fixed. If it is not OK, replace
the tone wheel and if it is OK, replace the speed sensor.
5D94 no acceleration after pressure reduction: Faulty sensor or missing sensor/tone wheel or ex-
cessive distance between the sensor and the tone wheel.
Troubleshooting: Check that the speed sensor and the tone wheel are installed. If they are not, install
them. If they are, check the speed sensor retainer. If it is not OK, restore it. If it is, check if the tone
wheel has the correct number of teeth or if it is dirty, deformed or wrongly fixed. If it is not OK, replace
the tone wheel and if it is OK, replace the speed sensor.
5D95 excessive speed measured: Faulty sensor or tone wheel, or tone wheel with wrong number of
teeth or wrong tyre size.
ELE SYS - 118
Moto Guzzi California 1400