VESPA 946 E4 EMEA 2021 Manual page 121

Vespa 946 E4-E5 EMEA-USA-ASIA (2021-)
reach a high operating temperature: that is why
there is a heating circuit inside.
Pin-out:
1. Heater supply (1)
2. Heater ground (2)
3. Sensor signal + (3)
4. Sensor signal - (4)
ELECTRICAL ERRORS
Check the air-fuel ratio / Lambda probe P0130 - short circuit to positive / open circuit, short circuit to
negative or mixture excessively lean / signal not plausible for abnormal title correction or probe signal
fault.
Error cause
Short-circuit to positive: excessive voltage at PIN 11 or PIN 12 of the control unit connector.
Open circuit or short-circuit to negative: interruption of the circuit or null voltage between control unit
connector PIN 11 and 12.
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 11); if there is a short, restore the wiring harness.
- Verify that there is no short to battery positive on sensor connector PIN 4 (corresponding to control
unit connector PIN 12); if there is a short, restore the wiring harness.
Open circuit:
- Disconnect the control unit connector and the sensor connector.
- Check the continuity of the wiring harness between the sensor connector and control unit connector:
Control unit PIN 11 - sensor PIN 3 and control unit PIN 12 - sensor PIN 4. If necessary, restore the
wiring harness.
- If the wiring harness is intact and the error persists, proceed with the following checks.
Short circuit to negative:
- Disconnect the sensor connector and the control unit connector.
- Check the sensor connector PIN 3 from ground insulation. If there is no insulation, restore the wiring
harness.
- Check the sensor connector PIN 4 from ground insulation. If there is no insulation, restore the wiring
harness.
- If PIN 3 and PIN 4 are insulated from the ground and the error persists, this means that there is a
probable fault in the control unit.
P0135 Lambda probe heating - shorted to positive / shorted to negative / open circuit.
Error cause
Electrical system
ELE SYS - 121