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DTC P1388: Auto Shutdown Relay Control Circuit: Testing

  1. Turn ignition on, with engine off. Using scan tool, actuate Auto Shutdown (ASD) relay. ASD relay is located in Power Distribution Center (PDC). PDC is located in engine compartment, next to battery. See Figure . If ASD relay is clicking, go to next step. If ASD relay is not clicking, go to step  4 .
  2. Turn ignition off. Inspect related connectors and wiring harness for damage. Repair connectors and wiring harness as necessary. If connectors and wiring harness are okay, go to next step.
  3. Start engine and allow it to idle. Wiggle wiring harness from ASD relay to PCM. PCM is located in engine compartment on left front fender, near radiator support. If engine stalls while wiggling wiring harness, repair wiring harness as necessary where wiggling caused engine to stall. If engine does not stall while wiggling wiring harness, no problem is indicated at this time. Test is complete.
  4. Turn ignition off. Remove ASD relay. Turn ignition on, with engine off. Using a voltmeter, measure voltage between ground and terminal D4 (Dark Blue/White wire) at ASD relay socket in PDC. See Figure . If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, check for repair open in Dark Blue/White wire between ASD relay and PDC. Also check fuse No. 11 (20-amp) in junction block. Junction block is located behind passenger side kick panel. Repair wiring or replace fuse as necessary.
  5. Turn ignition off. Measure resistance between terminals No. 85 and 86 at ASD relay. See Fig 1 . If resistance is less than 100 ohms, go to next step. If resistance is 100 ohms or more, replace ASD relay.
  6. Ensure ignition is off. Disconnect PCM connectors. PCM is located in engine compartment on left front fender, near radiator support. Inspect connectors for damaged pins, corrosion and loose terminals. Repair connectors as necessary. If connectors are okay measure resistance between ground and terminal No. 3 (Dark Blue/Yellow wire) at PCM C3 connector. See Figure . If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair short to ground in Dark Blue/Yellow wire between ASD relay and PCM.
  7. Measure resistance of Dark Blue/Yellow wire between terminal D6 at ASD relay socket in PDC and terminal No. 3 at PCM C3 connector. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Dark Blue/Yellow wire between ASD relay and PCM.
  8. At this time, PCM is assumed to be defective. Replace PCM.
Fig 1: Identifying Auto Shutdown Relay & Radiator Fan Relay Terminals
G99J08326Courtesy of DAIMLERCHRYSLER CORPORATION
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