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 CAMSHAFT POSITION (CMP) SENSOR INSPECTION [L8, LF, L3]

CAMSHAFT POSITION (CMP) SENSOR INSPECTION [L8, LF, L3]


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Note
• Perform the following inspection according to the DATA MONITOR function (indicated by monitor item from here onwards).

Visual Inspection

1. Disconnect the negative battery cable.

2. Remove the CMP sensor. (See CAMSHAFT POSITION (CMP) SENSOR REMOVAL/INSTALLATION [L8, LF, L3].)

3. Verify that there are no metal shavings on the sensor.

• If the monitor item condition/specification (reference) is not within the specification even though there is no malfunction, carry out the "Circuit Open/Short Inspection".

Voltage inspection

1. Idle the engine.

Caution
• Water penetrating the connector will cause sensor malfunction. To prevent this, be careful not to damage the wiring harnesses or the waterproof connector so as to cause water penetration.

2. Measure the output voltage using a oscilloscope.

• If not within the specification, replace the CMP sensor.
• If the monitor item condition/specification (reference) is not within the specification, even though the voltage is within the specification, carry out the "Circuit Open/Short Inspection".

Voltage

Terminal

Voltage (V)

Condition

A
B+
Under any condition
B
4.8 or more
High output*
0.8 or less
Low output*
C
0
Under any condition

* :
Output voltage varies with camshaft rotation.

Circuit Open/Short Inspection

1. Inspect the following wiring harnesses for an open or short circuit. (Continuity check)

Open circuit

• If there is no continuity, the circuit is open. Repair or replace the wiring harness.
- CMP sensor terminal A and body ground
- CMP sensor terminal B and PCM terminal 2S
- CMP sensor terminal C and PCM terminal 2AM

Short circuit

• If there is continuity, the circuit is shorted. Repair or replace the wiring harness.
- CMP sensor terminal A and power supply
- CMP sensor terminal B and power supply
- CMP sensor terminal B and body ground
- CMP sensor terminal C and power supply