Wiring connectors

Wiring connectors

The numbers in squares indicate the corresponding control unit pins.

Pin A - Earth
Pin B – Positive
Pin C – Signal

Checking the resistance

Sensor resistance may be measured as follows:

• connect an ohmmeter across sensor pins A and B and check a fixed resistance of 1200 ohms;
• check an ohmmeter between sensor pins A and C and check that resistance varies from 0 to 1200 ohm ± 20% when the throttle is moved.

Recovery

The system assumes a value calculated on the basis of rpm and pressure in the inlet manifold. If the pressure sensor fails at the same time, a throttle opening of about 50° is assumed as a fixed value.

Strategies to gradually decrease rpm at idle speed (dashpot) are blocked.

Idle speed self-adaption is blocked.

Mixture concentration self-adaption is blocked.

Removing-refitting

Procedure for premodification cars

Disconnect the electrical connection, undo the two fixing bolts and remove the sensor.

NOTE The sensor is secured to the throttle body by two tabs with two non-slotted holes. Sensor angular position does not require adjustment because the control unit recognises throttle closed or fully open positions by means of special self-adaptive algorithms.

NOTE Whenever the potentiometer bolts are loosened or removed, they must be replaced because the threads are covered by a light layer of loctite. This secures the bolt once only.

NOTE On post-modification cars, the throttle valve position sensor is built into the throttle body.