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Test NB - Code 88 Continuously Flashing

Visually inspect all wiring, wiring harness, connectors and other related components for damage.

  1. Measure STI Voltage At ECA: Install breakout box and turn ignition on. Using DVOM on 20-volt scale, measure voltage between pins No. 48 and 40 (ground). If reading is less than 10 volts, proceed to nest step. If reading is 10 volts or greater, proceed to step 5).
  2. Check STI Continuity To ECA: Install breakout box and unplug ECA. Turn ignition off. Using DVOM on 200-ohm scale, measure resistance between pin No. 48 and STI Yellow wire connector. If reading is less than 5 ohms, proceed to next step. If reading is 5 ohms or more, repair Yellow wire between ECA and Self-Test Input (STI) connector.
  3. Check STI For Short To Ground: Install breakout box and unplug ECA. Turn ignition off. Using DVOM on 200,000-ohm scale, measure resistance between pin No. 48 and ground pins No. 20, 40 and 49. If reading is greater than 10,000 ohms, proceed to next step. If reading is 10,000 ohms or less, repair short to ground.
  4. Check STI For Short To VPWR: Install breakout box and unplug ECA. Turn ignition on. Using DVOM on 20-volt scale, measure voltage between pins No. 48 and 40 (ground). If reading is greater than zero volts, repair short to VPWR. If reading is zero volts, replace ECA.
  5. Measure STO Voltage At ECA: Install breakout box. Jumper STI connector to ground. Turn ignition on and wait 10 seconds. Using DVOM on 20-volt scale, measure voltage between pins No. 17 and 40 (ground). If reading is less than 10 volts, proceed to next step. If reading is 10 volts or more, proceed to step 9).
  6. Check STO Continuity To ECA: Install breakout box and unplug ECA. Turn ignition off. Using DVOM on 200-ohm scale, measure the resistance between pin No. 17 and Self-Test Output (STO) Green/ Black wire connector. If reading is less than 5 ohms, proceed to next step. If reading is 5 ohms or more, repair Green/Black wire between ECA and STO connector.
  7. Check STO For Short To Ground: Install breakout box and unplug ECA. Turn ignition off. Using DVOM on 200,000-ohm scale, measure resistance between pin No. 17 and ground pins No. 20, 40 and 49. If readings are greater than 10,000 ohms, proceed to next step. If readings are 10,000 ohms or less, repair short to ground.
  8. Check STO For Short To VPRW: Install breakout box and unplug ECA. Turn ignition on. Using DVOM on 20-volt scale, measure voltage between pins No. 17 and 40 (ground). If reading is greater than zero volts, repair short to VPWR. If reading is zero volts, replace ECA.
  9. Measure SML Voltage At ECA: Install breakout box and turn ignition on. Wait 10 seconds and Using DVOM on 20-volt scale, measure voltage between pins No. 38 and 40 (ground). If reading is less than 10 volts, proceed to next step. If reading is 10 volts or more, proceed to step 13).
  10. Check SML Continuity To ECA: Install breakout box and unplug ECA. Turn ignition off. Using DVOM on 200-k/ohm scale, measure resistance between pin No. 38 and STO Red/Blue wire. If reading is less than 5 ohms, proceed to next step. If reading is 5 ohms or greater, repair Red/Blue wire between ECA and STO connector.
  11. Check SML For Short To Ground: Install breakout box and unplug ECA. Turn ignition off. Using DVOM on 200-k/ohm scale, measure resistance pin No. 38 and ground pins No. 20, 40 and 49. If reading is greater than 10,000 ohms, proceed to next step. If reading is 10,000 ohms or less, repair short to ground.
  12. Check SML For Short To VPWR: Install breakout box and unplug ECA. Turn ignition on. Using DVOM on 20-volt scale, measure voltage between pins No. 38 and 40 (ground). If reading is greater than zero volts, repair short to VPWR. If reading is zero volts, replace ECA.
  13. Measure Voltage At Self-Test Connector: Turn ignition on. Using DVOM on 20-volt scale, measure voltage between STO Yellow/ Green wire connector and ground. If reading is less than 10 volts, proceed to next step. If reading is 10 volts or more, proceed to TEST B  .
  14. Measure Voltage From Power Relay: Turn ignition on. Power relay should remain connected. Using DVOM on 20-volt scale, measure voltage between power relay Yellow/Green wire and ground. If reading is less than 10 volts, proceed to TEST FC  . If reading is 10 volts or more, repair Yellow/Green wire between STO connector and power relay.
Fig 1: Self-Test Connector Circuit
G94557
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