TIAGO

1.2L REVOTRON ENGINE

152

III. Camshaft Position Sensor :



Component Details :

A typical Hall Effect Sensor has three wires or

terminals: one for ground, one for supply or

reference voltage and one for the output signal.

To produce an output signal, a Hall Effect Sensor

must be supplied with a reference voltage. When

a metal/wheel passes through the air gap

between the magnetic field (Magnet) and silicon

chip (CAM sensor), it blocks the magnetic field

and causes the chip’s output voltage to suddenly

drop to zero else the chip's output voltage is 4.7

Volts.



Component Location :

The cam phase sensor is mounted on

cylinder head.



Preliminary Checks :

1. Loose / Damaged connections between

sensor and EMS ECU.

2. Check for back out of pins at both sensor

connector and ECU connector.

3. Check for damage of pins at both sensor

connector and ECU connector.

4. Check the continuity from sensor

connector pins to the ECU pins.

5. Physical damage to Cam target wheel.

6. Improper air gap between sensor and

cam target wheel.



Connector View :



Connector Details :

Connector

Description

Ground (-)

Signal

Supply (+)



Component Specification :

Cam Shaft sensor measures the speed of the

CAM shaft. The cam phase sensor is mounted on

cylinder head cover, with a gap of 1.0± 0.5mm

between cylinder head cover surface and sensor

tip. The sensor provides input signal to ECU to

determine the phase, i.e. the sensor provides

signal voltage when the target wheel passes

through the sensor. The position of target wheel

indicates the engine phase. Cam shaft sensor

contains a permanent magnet and a Hall IC. Due

to the rotation of a ferromagnetic target wheel in

front of Sensor, the magnetic field is modulated at

the place of the hall probe. With a tooth in front of

the sensor, the magnetic field increases, with a

slot it decreases. This modulation results in

changes of the output signal. The magnetic field is

evaluated by the hall probe in the ASIC.



Sensor Stand alone Diagnosis :

With ignition key is 'ON' position, use multimeter

to measure the supply voltage across pin1 and

pin3, which should be 12V DC.

Measure the signal voltage across pin1 and pin2.