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Test D - No/Wrong Codes

  1. Turn ignition off and wait 10 seconds. Place DVOM on 20 volt scale. Disconnect throttle position sensor (TPS). Turn ignition on. Measure voltage at TPS harness connector between voltage reference signal circuit and signal return circuit. If 6 volts or more, to TEST C  , step 2). If less than 4 volts, to TEST C  , step 1). If between 4-6 volts, reconnect TPS and go to next step.
  2. With ignition on, measure voltage between battery negative post and signal return circuit in Self-Test connector. If less than .5 volt, go to next step. If .5 volt or more, go to TEST B  , step 4).
  3. Turn ignition off and wait 10 seconds. Disconnect 60-pin connector at ECA and inspect. Repair as required. Connect breakout box and reconnect ECA. Place DVOM on 200 ohm scale. Measure resistance of Self-Test input connector from Self-Test pigtail to box pin 48. If less than 5 ohms, go to next step. If 5 ohms or more, repair open circuit and repeat QUICK TEST  .
  4. Measure resistance of Self-Test output between Self-Test connector and box pin 17. If less than 5 ohms, go to next step. If 5 ohms or more, repair open circuit and repeat QUICK TEST  .
  5. Turn ignition off. Connect DVOM between oxygen sensor ground point on engine and box pin 49. If 5 ohms or more, repair oxygen sensor ground wire or open circuit bad connection and repeat QUICK TEST  . If less than 5 ohms, disconnect ECA and inspect connector. If okay, reconnect and repeat QUICK TEST  . If problem still present, replace ECA.
  6. Continuous Code 15. Code 15 is recorded any time power is lost to Keep Alive Memory circuit. Clear continuous codes and repeat KEY ON-ENGINE OFF (KOEO) SELF-TEST  . If code 15, go to next step. If no code 15, test complete.
  7. Ensure EEC components are properly connected and wiring does not contact ignition components or wires. Service as required and repeat KEY ON-ENGINE OFF (KOEO) SELF-TEST  . If code 15, go to next step. If no code 15, test complete.
  8. Check power circuit to Keep Alive Memory circuit for voltage. Turn ignition off and wait 10 seconds. Disconnect 60-pin connector at ECA and check connector terminals and ECA pins for damage. Connect breakout box, leaving ECA disconnected. With DVOM on 20 volt scale, connect positive lead to box pin 1 and negative lead to pin 46. Turn ignition on and observe reading. If less than 10 volts, service open to Keep Alive Memory circuit and repeat QUICK TEST  . If 10 volts or more, go to next step.
  9. With ignition on, activate KEY ON-ENGINE OFF (KOEO) SELF-TEST  . If code 15, replace ECA and repeat QUICK TEST  . If no code 15, disconnect breakout box and repeat KEY ON-ENGINE OFF (KOEO) SELF-TEST 
  10. Engine Stalls Routine. Perform diagnosis of non-EEC related components and repair as required. Check all vacuum lines, electrical connections and routing. Diagnose engine functions as on a vehicle without EEC. After correcting faults, go to next step.
  11. Turn ignition off and wait 10 seconds. Install tachometer. Start engine and attempt to maintain engine at 2000 RPM for 2 minutes. If engine stalls, go to TEST A  , step 13). If engine does not stall, go to next step.
  12. With engine at operating temperature and tachometer installed, turn ignition off and wait 10 seconds. Activate QUICK TEST  and perform KEY ON-ENGINE RUNNING (KOER) SELF-TEST  while maintaining engine at 2000 RPM. If engine passes test or any codes are recorded, service codes as described for Engine Running Self-Test. If no codes are recorded, go to step  1 .
  13. Output State Check Not Functioning. Turn ignition off and wait 10 seconds. Perform KEY ON-ENGINE OFF (KOEO) SELF-TEST  and leave ignition on to enter Output State Check. If codes 23, 53, 63, or 68 are present in On Demand Test results, service codes as described for Key On-Engine Off Self-Test. If no codes 23, 53 or 63, leave ignition on and go to next step.
  14. While in Output State Check, set DVOM on 20 volt scale. Measure voltage between Self-Test output circuit of Self-Test connector and battery positive terminal. Depress throttle to wide open position and release. Verify throttle is in closed position and note voltage reading. If greater than 10 volts, check throttle and linkage for sticking or binding and repeat QUICK TEST  . If less than 10 volts, replace throttle position sensor (TPS) and repeat QUICK TEST  .
Fig 1: No Codes/Invalid Codes Circuit Diagram
G9338
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