Mazda 323 1988 Workshop Manual page 402

KNOCKCONiROLSYSTEM 5
connector
4. Disconnect the service connector.
5. Disconnect the knock sensor connector and check
that the ignition timing retards.
6. Reconnect the knock sensor connector and cof-
nirm that the ignition timing returns to specification.
Specification: 12 * lo BTDC
INSPECTION OF KNOCK SENSOR
1. Check the retard function.
2. If the ignition timing does not retard, go to next step.
3. Disconnect the knock sensor connector.
4. Connect a good knock sensor to the vehicle and
ground the sensor.
5. Tap the sensor and make sure the ignition timing
retards.
6. If the retard operates, replace the knock sensor.
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