Vespa GTS Super 300 ie - Service manual > Diagnostic instrument

STARTER COMMAND

Function

Commands engine starting through the injection control unit.

Operation / Operating principle

The starter button, the brake switches, the starter relay and the injection control unit through PIN 10 are involved.

ELECTRICAL ERRORS

Starter command P0170 - shorted to positive

Error cause

Shorted to positive: excessive voltage at PIN 10 of the control unit connector.

Troubleshooting

Short circuit to positive:

COIL

Function

Allows generation of the electrical discharge on the spark plug, with an increase of voltage.

Pinout:

  1. Power from relay
  2. Activation by control unit (control unit side PIN 1)

Electrical System

ELECTRICAL ERRORS

H.V. Coil P0351 - shorted to positive / open circuit or shorted to negative.

Error cause

Shorted to positive: excessive voltage at PIN 1 of the control unit connector.

Circuit open or short circuit to negative:interruption of the circuit or null voltage at PIN 1 of the control unit connector.

Troubleshooting

Short circuit to positive:

Open circuit:

Short circuit to negative:

INJECTOR

Function

Provide the correct amount of fuel at the correct time.

Operation / Operating principle

Injector coil is excited for the petrol passage to open.

Pinout:

  1. Power from relay
  2. Ground from control unit

Electrical System

ELECTRICAL ERRORS

Injector P0201 - shorted to positive / shorted to negative / open circuit.

Error cause

Shorted to positive: excessive voltage to PIN 34 of the control unit connector.

Shorted to negative: zero voltage to the PIN 1 of the injector connector.

Open circuit: circuit interruption.

Troubleshooting

Shorted to positive:

Shorted to negative:

Open circuit:

FUEL PUMP

ELECTRICAL ERRORS

Fuel pump relay P0230 - shorted to positive / shorted to negative / open circuit.

Error cause

Shorted to positive: excessive voltage at PIN 22 of the control unit connector.

Short circuit to negative: null voltage at PIN 86 of the injection relay.

Open circuit: circuit interruption.

Troubleshooting

Short circuit to positive:

Short circuit to negative:

Open circuit:

If necessary, restore the cable harness.

ELECTRIC FAN CIRCUIT

Function

Radiator fan and coolant - Operation.

Operation / Operating principle

The control unit closes the fan control relay excitation circuit to ground until the temperature drops.

ELECTRICAL ERRORS

Fan relay P0480 - shorted to positive / shorted to negative / open circuit.

Error cause

Shorted to positive: excessive voltage at PIN 24 of the control unit connector.

Shorted to negative: null voltage at PIN 24 of the control unit connector.

Open circuit: circuit interruption.

Troubleshooting

Short circuit to positive:

Short circuit to negative:

Open circuit:

ENGINE TEMPERATURE SENSOR

Function

Serves the purpose of communicating the engine temperature to the control unit in order to optimise performance.

Operation / Operating principle

NTC type sensor (resistance sensor, inversely variable with temperature).

Pinout:

  1. Ground from control unit
  2. Instrument panel
  3. Injection ECU
  4. Ground lead

Electrical System

Engine temperature sensor P0115 - open circuit or shorted to positive / shorted to negative.

Error cause

Open circuit or short circuit to positive:interruption of the circuit or excessive voltage at PIN 13 of the control unit connector. Short circuit to negative: null voltage between PIN 13 and 7 of the control unit connector.

Troubleshooting

Open circuit:

Short circuit to positive:

Short circuit to negative:

LAMBDA PROBE

Function

In charge of telling the control unit whether the mixture is lean or rich.

Operation / Operating principle

Based on the difference of oxygen in the exhaust fumes and the environment, this generates voltage which is read and interpreted by the injection control unit.

Pinout:

  1. Signal to the control unit (+)
  2. Signal to the control unit (-)

Electrical System

ELECTRICAL ERRORS

Check the air-fuel ratio / Lambda probe P0130 - short circuit to positive / open circuit, short circuit to negative or carburetion excessively lean / signal not plausible for abnormal title correction or probe signal fault.

Error cause

Short circuit to positive: excessive voltage to PIN 11 or PIN 12 of the control unit connector. Open circuit or short circuit to negative: interruption of the circuit or zero voltage between the pins 11 and 12 of the control unit connector.

Troubleshooting

Short circuit to positive:

Open circuit:

Short circuit to negative:

See also:

 Vespa GTS Super 300 ie - Service manual > Connectors

DIAGNOSTICS CONNECTOR Not connected Ground lead (Black) Electronic control unit (Violet - White)

 Vespa GTS Super 300 ie - Service manual > Engine from Vehicle

Exhaust assy. Removal Remove the right and left fairings and the spoiler terminals. Remove the Lambda probe from its support and disconnect it.

Maxi Scooters: