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Test Dr - Cylinder Identification (CID) Sensor

You should enter this CIRCUIT TEST only when Code 19 is received during QUICK TEST. This test is intended to diagnose only the following:

  1. 1) Continuous Memory Code 19: Check CID Sensor Resistance -  Code 19 indicates and error has been detected in the CID sensor input signal. The error could be due to a hard fault or intermittent condition. Possible causes for this fault are an open or shorted harness, a faulty CID sensor or a faulty ECA. With key off, disconnect CID sensor (located on back of cylinder head coil pack). Set DVOM on 200-k/ohm scale. Measure resistance of CID sensor. If resistance is 300-600 ohms, go to next step. If not, replace CID sensor and repeat QUICK TEST.
  2. 2) Check Continuity of CID Circuits -  With key off, and CID sensor disconnected, disconnect ECA 60-pin connector. Inspect and repair any corroded or damaged pins. Install breakout box, leaving ECA disconnected. Set DVOM on 200-k/ohm scale. Measure resistance between test pin No. 41 and CID (+) circuit at the CID sensor vehicle harness connector. Measure resistance between test pin No. 42 and CID (-) at the CID sensor vehicle harness connector. If each resistance is less than 5 ohms, go to next step. If not, repair open circuit as necessary, remove breakout box and reconnect all components. Repeat QUICK TEST.
    Fig 2: Checking CID Sensor Harness Circuit
    G90E12413
  3. 3) Check CID Circuit For Shorts -  With key off, and breakout box installed, ensure ECA and CID sensor are disconnected. Set DVOM on 200-k/ohm scale. Measure resistance between test pin No. 41 and test pins No. 42, 37, 57, 40, and 60. Measure resistance between test pin No. 42 and test pins No. 37, 57, 40, and 60. If each resistance is greater than 10 k/ohms, go to next step. If not, repair short circuit, remove breakout box and reconnect all components. Repeat QUICK TEST.
  4. 4) Check For Shorts in ECA -  With key off, install breakout box and reconnect ECA. Disconnect CID sensor. Set DVOM on 200-k/ohm scale. Measure resistance between test pin No. 41 and test pins No. 42, 37, 57, 40, and 60. Measure resistance between test pin No. 42 and test pins No. 37, 57, 40, and 60. If each resistance is greater than 500 ohms, go to next step. If not, replace ECA, remove breakout box and reconnect all components. Repeat QUICK TEST.
  5. 5) Check CID Sensor Output -  With key off, breakout box installed and ECA connected, reconnect CID sensor. Set DVOM on AC 5-volt scale. Start engine. Measure voltage between test pins No. 41 and 42 while varying engine RPM. If voltage varies, go to next step. If not, replace CID sensor, remove breakout box and reconnect components. Repeat QUICK TEST.
  6. 6) Attempt to Regenerate Code 19 -  With KOEO, clear Continuous Memory Codes. Start engine. Rev engine to 3100+ RPM, 2 or 3 times. Turn key off. Repeat KOEO Self-Test. If Continuous Memory Code 19 is still present, replace ECA, remove breakout box, reconnect all components and repeat QUICK TEST. If not, Code 19 is an intermittent fault. Check vehicle harness for intermittent opens or shorts. See INTERMITTENTS in TESTS W/O CODES article.
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