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Test N - Code 12/Rpm Test

  1. If codes 31, 41 and/or 58 are present, perform appropriate tests before proceeding.
  2. Check throttle plates and linkages for binding. Check speed control (if equipped) for binding. If any trouble is found, correct as necessary and repeat Quick Test. If no trouble is found, proceed with test.
  3. Turn ignition off and wait 10 seconds. Disconnect processor and inspect both 60 pin connectors. Connect breakout box to harness and processor. Disconnect ISC connector. Measure continuity from circuit 95 to breakout box pin 41 and circuit 96 to breakout box pin 21. If either resistance is 5 ohms or more, repair wiring harness and repeat Quick Test. If both resistances are less than 5 ohms, proceed with test.
  4. Disconnect processor. Turn ignition on. Measure voltage from breakout box pin 41 to pins 40 and 60. Measure voltage from breakout box pin 21 to pins 40 and 60. If any voltage reading is 1 volt or more, repair short to power circuit and repeat Quick Test. If code 12 is still present, replace processor. If all voltage readings are less than 1 volt, proceed with test.
  5. Disconnect processor. Measure resistance from breakout box pin 41 to pins 40, 46 and 60. Measure resistance from breakout box pin 21 to pins 40, 46 and 60. If any resistance reading is 10,000 ohms or less, repair faulty circuit and repeat Quick Test. If code 12 is still present, replace processor. If all resistance readings are more than 10,000 ohms, proceed with test.
  6. Disconnect processor. Turn ignition off and wait 10 seconds. Connect voltmeter positive lead to breakout box pin 1 and negative lead to ground. If voltage is less than 10.5 volts, repair open circuit and repeat step 6) if code 12 is still present. If voltage is 10.5 volts or more, proceed with test.
  7. Turn ignition off and wait 10 seconds. Reconnect ISC motor. Jumper breakout box pin 21 to pin 1 and pin 41 to ground. Check ISC motor for extension of shaft. If motor shaft extends less than 2", replace ISC motor and repeat Quick Test. If shaft extends 2" or more, proceed with test.
  8. Turn ignition off and wait 10 seconds. Jumper breakout box pin 41 to pin 1 and pin 21 to ground. Check ISC motor for retraction. If shaft does not retract, replace ISC motor and repeat Quick Test. If shaft retracts, proceed with test.
  9. Turn ignition off and wait 10 seconds. Jumper breakout box pin 21 to pin 1 and pin 41 to ground. Check ISC motor for extension of shaft. If motor shaft does not extend, replace ISC motor and repeat Quick Test. If shaft extends, replace processor and repeat Quick Test.
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