MOTO GUZZI 2Q000297 Service Station Manual page 124

Electrical system
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Disconnect the sensor connector and the control unit connector.
•
Check the sensor connector PIN 1 ground insulation. In the absence of insulation restore
the wiring harness.
•
Check the sensor connector PIN 2 ground insulation. In the absence of insulation restore
the wiring harness.
•
If PIN 1 and PIN 2 are insulated from the ground and the error persists, this means that there
is a probable fault in the control unit.
Lambda probe heater P0135 - shorted to positive / shorted to negative / open circuit.
Error cause
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Short-circuit to positive: excessive voltage at PIN 31 of the control unit connector
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Short-circuit to negative: lack of insulation from ground on the sensor connector PIN 4
•
Open circuit: circuit interruption.
Troubleshooting
Short-circuit to positive:
•
Disconnect the control unit connector and the sensor connector.
•
Verify that there is no short to battery positive on sensor connector PIN 3 (corresponding to
control unit connector PIN 31); if there is a short, restore the wiring harness.
Short-circuit to negative:
•
Disconnect the sensor connector.
•
Check the sensor connector PIN 3 ground insulation. In the absence of insulation restore
the wiring harness.
•
If PIN 3 is insulated from ground and in the absence of other errors (fuel pump, injector, coil),
this means that the control unit is most likely faulty.
Open circuit:
•
Disconnect the control unit connector and the sensor connector.
•
Verify continuity of the wiring harness between the sensor connector and the control unit
connector: Control unit PIN 31 - sensor PIN 3. If necessary, restore the wiring harness.
•
Verify continuity of the wiring harness between the sensor connector and the injection relay:
sensor PIN 4 - injection relay PIN 3. If necessary, restore the wiring harness.
•
If the wiring harness is intact and the error persists, proceed with the following checks.
ELE SYS - 124
V7 III ABS