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Diagnostic Procedures

  1. Install scan tool. Turn ignition on. Using scan tool, monitor TP sensor, MAP and EGR voltages. If they all read less than .24 volt, go to next step. If MAP voltage is greater than 5.1 volts, go to step 4). If MAP voltage is not greater than 5.1 volts, problem is intermittent. See DIAGNOSTIC AIDS.
  2. Turn ignition off. Disconnect PCM harness connector J2. Using a test light connect to battery voltage, probe PCM harness connector terminals J2B04 and J2B05. If test light illuminates, go to next step. If test light does not illuminate, replace PCM.
  3. Disconnect MAP, EGR, and TP sensor one at a time. If test light goes out when disconnecting a component, replace that component. If test light stays on, repair short to ground in affected circuit.
  4. Turn ignition off. Disconnect PCM harness connector J2. Turn ignition on. Check voltage on PCM harness connector terminals J2B04 and J2B05. If voltage is present, repair short to voltage in affected circuits. If voltage is not present, replace PCM.
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