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Code 22 - Knock Sensor

NOTE: Refer to illustration for ECU connector and terminal identification. See Figure .
  1. Turn ignition on. Measure voltage between ECU connector B56, terminal No. 5 (backprobe) and ground. If voltage is not 3-4 volts, check ECU terminals for poor contact or replace ECU. If 3-4 volts are present, go to next step.
  2. Turn ignition off. Disconnect knock sensor connector. Measure resistance between knock sensor connector terminal and ground. If about 560,000 ohms are present, go to next step. If about 560,000 ohms are not present, replace knock sensor.
  3. Disconnect ECU and knock sensor connectors. Measure resistance between ECU connector B56, terminal No. 5 and knock sensor connector. Zero ohms should be present. Measure resistance between knock sensor connector terminal and ground. At least one megohm should be present. If resistances are not to specification, repair harness or connector. If resistances are to specification, check ECU terminals for poor contact or replace ECU.
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