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Circuit Test D14

NOTE: Perform this CIRCUIT TEST when directed by other test procedures.
Fig 1: No Codes/Codes Not Listed Circuits (1 of 3)
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Fig 2: No Codes/Codes Not Listed Circuits (2 of 3)
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Fig 3: No Codes/Codes Not Listed Circuits (3 of 3)
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  1. Checking For VREF. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair if necessary. Install breakout box, and connect ECA. Set DVOM on 20-volt scale. With KOEO, measure voltage between test pin No. 26 and SIGNAL RETURN at Self-Test connector. If reading is less than 4 volts or more than 6 volts, go to CIRCUIT TEST A3 , step 1). If reading is between 4 and 6 volts, go to next step.
  2. Checking SELF-TEST Input Continuity. Turn key off and wait 10 seconds. With breakout box installed and ECA disconnected. Set DVOM on 200-ohm scale. Measure resistance between test pin No. 48 at the breakout box and Self-Test Input (STI) at SELF-TEST connector pigtail. If reading is 5 ohms or more, repair open in circuit, remove breakout box and reconnect ECA. Rerun QUICK TEST. If reading is less than 5 ohms, go to next step.
  3. Checking SELF-TEST Output Circuit Continuity. With breakout box installed and ECA disconnected, set DVOM on 200-ohm scale. Measure resistance between test pin No. 17 at the breakout box and Self-Test Output (STO) at SELF-TEST connector. If reading is 5 ohms or more, repair open circuit, remove breakout box and reconnect ECA. Rerun QUICK TEST. If reading is less than 5 ohms, go to next step.
  4. Checking EGO Sensor Ground Continuity. Turn key off. With breakout box installed and DVOM on 200-ohm scale, measure resistance between test pin No. 49 and EGO GROUND on engine block. If reading is 5 ohms or more, repair EGO sensor ground wire or open circuit. If reading is less than 5 ohms, go to next step.
  5. Checking For STO Short to Ground. With breakout box installed and ECA disconnected, set DVOM on 200K-ohm scale. Measure resistance between STO at Self-Test connector and engine block ground. Rerun QUICK TEST. If reading is 10K ohms or less, repair STO or MIL/SIL circuit for short to ground and repeat QUICK TEST. If reading is greater than 10K ohms, go to step 7) for 3.8L AXOD vehicles. If reading is greater than 5 ohms, go to next step for all other engines.
  6. Intermittent: Neutral Drive Switch (NDS), No Codes Displayed. Turn key off. Install breakout box, and connect ECA to breakout box. Set DVOM on 20-volt scale. Connect DVOM between test pin No. 30 and test pins No. 40 or 60 at the breakout box. Refer to the circuit diagram in CIRCUIT TEST B13  for this step. Perform KOER SELF-TEST. If reading is greater than one volt, repair intermittent open in NDS harness connector or switch. If okay, reconnect ECA and go to KOER SELF-TEST for appropriate service codes. If reading is less than one volt, go to next step.
  7. Power Relay Always On. Leave key off and breakout box installed. Set DVOM on 20-volt scale. Connect DVOM between test pins No. 37 or 57 and pins No. 40 or 60. Turn key on and then off. Wait 10 seconds. If reading does not change from 10.5 volts (or more) to zero volts, go to next step. If reading changes from 10.5 volts (or more) to zero volts, go to step 9) only if vehicle is equipped with Malfunction Indicator Light (MIL) or Shift Indicator Light (SIL). If vehicle is NOT equipped with either of these lights, replace ECA and repeat QUICK TEST.
    NOTE: Malfunction Indicator Light (MIL) is displayed as "CHECK ENGINE" light on instrument cluster.
  8. VPWR Harness Short to Power. With key off, breakout box installed and EEC power relay or Integrated Relay Controller Module (IRCM) disconnected, set DVOM on 20-volt scale. Connect DVOM to test pin No. 37 or 57 and to test pin No. 40 or 46 at the breakout box. If voltage is greater than 10.5 volts, repair short to VPWR circuit and rerun QUICK TEST. If voltage is less than 10.5 volts, replace EEC-IV power relay or IRCM and rerun QUICK TEST.
  9. Malfunction Indicator Light (MIL) or Shift Indicator Light (SIL). If shift indicator light is always on or off, go to CIRCUIT TEST D6 , step 1). If malfunction indicator light is always on, go to CIRCUIT TEST D11 , step 1). If malfunction indicator light is always off, go to CIRCUIT TEST D11 , step 5). If MIL or SIL is working normally, replace ECA and repeat QUICK TEST.
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