Note: For additional information regarding the camshaft position sensor circuit, refer to chapter 5 in Illustration 9.21b.
General description
62. The camshaft position sensor is located on the timing chain cover behind the coolant pump next to the camshaft sprocket. When the camshaft rotates, the magnet attached to it changes the electromagnetic field. As a result, the electronic circuit shorts the signal circuit going to the PCM unit to ground, and the voltage in it drops sharply. This creates a signal "interruption" condition. If there is no signal from the camshaft position sensor, the PCM generates code 41.
Examination
63. To check the camshaft position sensor circuit, disconnect the sensor electrical connector (see illustration). Turn on the ignition, but do not start the engine.
4.63. Camshaft position sensor (shown by arrow) located on the timing chain cover (bottom view)
64. Measure the voltage between contacts "A" and "B" on the sensor connector. It should be within 5-7 V.
65. Measure the voltage between contacts "B" and "C" on the sensor connector. It should be within 8-11 V.
66. If the voltage between terminals "A" and "B" is below the specified limits, check the sensor electrical circuit for an open or short circuit. Also, check the serviceability of the ignition unit (see chapter 5, section 9).
67. If the voltage between contacts "B" and "C" is too low, check the condition of the wires running from these contacts to the corresponding points of the electrical circuit.
68. If in both cases the measured voltage values fall within the specified limits, take the camshaft sensor together with the PCM unit to a repair shop for inspection.
Replacement
69. Disconnect the cable from the negative terminal of the battery.
70. Remove the poly V-belt (see chapter 1, section 21).
71. Disconnect the electrical connector from the camshaft position sensor.
72. After unscrewing the bolt, remove the sensor from the timing chain housing.
73. The sensor is installed in the reverse order. After installation, make sure that the sensor mounting bolt is tightened to the required torque specified in the technical data at the beginning of the chapter.
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