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Test B - Vehicle Battery

  1. Turn ignition on, engine off. With DVOM on 20 volt scale, measure voltage across battery terminals. If more than 10.5 volts, go to next step. If less than 10.5 volts, service discharged battery.
  2. Ignition on, engine off. With DVOM on 20 volt scale, measure voltage between battery negative post to signal return circuit in self-test connector. If less than .5 volts, go to next step. If more than .5 volts, go to step  4 .
  3. Connect breakout box, ECA connected. Turn ignition on, engine off. With DVOM on 20 volt scale, measure voltage from battery positive post to pin box 37 and pin 57. If both readings are less than .5 volts, go to TEST C  . If either is more than .5 volts, go to step  7 .
  4. With breakout box and ECA connected, turn ignition on (engine off). With DVOM on 20 volt scale, measure voltage from battery negative post to box pin 40 and pin 60. If both readings are less than .5 volts, go to next step. If either is .5 volts or more, circuit has high resistance or open. Correct faulty ground circuit and repeat QUICK TEST  .
  5. With breakout box and ECA connected, place DVOM on 200 ohm scale. Turn ignition off and wait 10 seconds. Measure resistance between box pins 40 and 46, and between box pins 46 and 60. If both readings are less than 5 ohms, go to next step. If either is 5 ohms or more, disconnect ECA connector and inspect for damaged pins and corrosion. Repair as required and repeat QUICK TEST  . If fault is still present, replace ECA and repeat QUICK TEST  .
  6. With breakout box and ECA connected, place DVOM on 200 ohm scale. Turn ignition off and wait 10 seconds. Measure resistance between box pin 46 and signal return circuit in self-test connector. If less than 5 ohms, system okay, repeat QUICK TEST  . If 5 ohms or greater, excessive resistance in signal return circuit is indicated. Correct fault and repeat QUICK TEST  .
  7. Place DVOM on 20 volt scale. With ECA connected, turn ignition on. Connect DVOM negative lead to battery negative post and make the following voltage checks with DVOM positive lead. Ignition must remain on for these checks.
    • Keep alive power circuit at EEC power relay. If 10.5 volts or greater, continue checks. If less than 10.5 volts, check keep alive power and vehicle power circuits for shorts to ground. Check keep alive power circuit from power relay to battery positive post for opens.
    • Ignition circuit at EEC power relay. If 10.5 volts or greater, continue checks. If less than 10.5 volts, check 10 amp fuse in location 18. Check for opens in ignition switch circuits. Service as required and repeat QUICK TEST  .
    • Ground circuit at EEC power relay. If less than .5 volt, go to next check. If .5 volt or more, correct open or ground in ground circuit. Repeat QUICK TEST  .
    • Vehicle power circuit at EEC power relay. If 10.5 volts or more, correct short to ground or open in vehicle power circuit from relay to ECA connector pins 37 and 57. Repeat QUICK TEST  . If less than 10.5 volts, replace power relay and repeat QUICK TEST  .
Fig 1: Battery Test Circuits
G9336
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