DI±73
DIAGNOSTICS ± ENGINE
4 Does malfunction disappear when a good knock sensor 1 is installed?
YES | Replace knock sensor 1. |
NO
Check and replace ECM (See page IN±30).
Reference: INSPECTION USING OSCILLOSCOPE
KNK signal waveform | S | With the engine racing (4,000 rpm) measure between ter- | |
0.5V/ |
| minal KNK of the ECM connector and body ground. | |
Division |
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HINT: |
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0V | The correct waveforms are as shown. | ||
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| S | Spread the time on the horizontal axis, and confirm that | |
5 m sec./Division |
| period of the wave is 80 ∝ sec. | |
0.5V/ |
| (Normal mode vibration frequency of knock sensor: | |
| 12.5 kHz (1ZZ±FE), 7.1 kHz (2ZZ±GE)) | ||
Division | HINT: |
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0V | If normal mode vibration frequency is not 7.6 kHz the sensor is | ||
malfunctioning. | |||
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100 sec./Division |
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| A00406 |
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2000 CELICA (RM744U)
