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Home >> GMC >> 1991 >> Value Van 7.4 N >> Repair and Diagnosis >> External Pages >> Different car >> Section 27 (Engine Controls - Tests W/Codes - 3.0L) >> Self-Diagnostic Tests >> Test TC-28A - No ASD Relay Volt Sensed At Pcm (DTC 42)

Test TC-28A - No ASD Relay Volt Sensed At Pcm (DTC 42)

WARNING: This page is about a different car, the 1995 Plymouth Voyager, 1995 Plymouth Grand Voyager, 1995 Dodge Grand Caravan, and 1995 Dodge Caravan. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: For circuit and connector terminal identification, see CONNECTOR IDENTIFICATION  . For wiring diagrams, see WIRING DIAGRAMS  section.
  1. If this DTC is also set with AUTO SHUTDOWN RELAY CONTROL CIRCUIT DTC, go to TEST TC-29A. If AUTO SHUTDOWN RELAY CONTROL CIRCUIT DTC is not set, go to next step.
  2. Using scan tool, erase DTCs. Attempt to start and idle engine. Using scan tool, read DTCs. If scan tool displays NO ASD RELAY OUTPUT VOLTAGE AT PCM, go to step 7). If scan tool does not display NO ASD RELAY OUTPUT VOLTAGE AT PCM, go to next step.
  3. Condition required to set DTC is not present at this time. The NO ASD RELAY OUTPUT VOLTAGE AT PCM DTC sets if PCM does not detect ASD relay voltage when energized. Check following for possible causes: open ASD relay Dark Green/Orange wire, open ASD relay Red/White wire, failed ASD relay, or PCM failure. Go to next step.
  4. Inspect all related wiring and connectors. Repair as necessary. Perform TEST VER-2. If no problems are found with wiring and connectors, go to next step.
  5. Engine must be running before continuing with test. Wiggle wiring harness from ASD relay to Powertrain Control Module (PCM). Using scan tool, read DTCs. If scan tool displays NO ASD RELAY OUTPUT VOLTAGE AT PCM, repair wiring harness as necessary. Perform TEST VER-2.
  6. If scan tool does not display NO ASD RELAY OUTPUT VOLTAGE AT PCM, see INACTIVE DTC CONDITION. Perform TEST VER-2.
  7. If engine starts, go to step 10). If engine does not start, disconnect ASD relay. Using scan tool in voltmeter mode, check voltage on ASD relay connector terminal "B" (Red/White wire). If voltage is less than 10 volts, repair open Red/White wire. Perform TEST VER-2.
  8. If voltage is more than 10 volts, install a known-good ASD relay. Attempt to start engine. If engine starts, replace original ASD relay. Perform TEST VER-2. If engine does not start, turn ignition off.
  9. Disconnect PCM connector. Using an external ohmmeter, check resistance of Dark Green/Orange wire between ASD relay connector and PCM connector terminal No. 57. If resistance is more than 5 ohms, repair open Dark Green/Orange wire. Perform TEST VER-2. If resistance is less than 5 ohms, replace PCM. Perform TEST VER-2.
  10. Turn ignition off. Disconnect PCM connector. Using an external ohm-meter, check resistance of Dark Green/Orange wire between ASD relay connector and PCM connector terminal No. 57. If resistance is more than 5 ohms, repair open Dark Green/Orange wire. Perform TEST VER-2. If resistance is less than 5 ohms, replace PCM. Perform TEST VER-2.
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