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No Response From ACM

WARNING: Air Bag Control Module (ACM) retains energy for up to 2 minutes after battery is disconnected. Air bag may deploy. Wait at least 2 minutes after disconnecting battery in following test.
CAUTION: Caution should be used when servicing air bag system components. For air bag system component removal and installation procedures, see AIR BAG RESTRAINT SYSTEMS - CARS article.
NOTE: After making any repairs, perform AIR BAG VERIFICATION TEST  under VERIFICATION TESTS unless instructed otherwise in following steps.
NOTE: Unless instructed otherwise in test step, reconnect any disconnected connectors.
  1. Turn ignition off. Disconnect negative battery cable and wait at least 2 minutes before proceeding. Disconnect ACM connector. Check, clean and repair connectors as necessary. Using an ohmmeter, check resistance between ground and ACM (component side) terminal No. 4 (Black/Pink wire on wiring harness side). See Fig 1. If resistance is less than 5 ohms, leave ACM connector disconnected and go to next step. If resistance is 5 ohms or more, replace ACM. See AIR BAG RESTRAINT SYSTEMS - CARS article.
    Fig 1: Identifying Air Bag Control Module (ACM) Connector Terminals (Wiring Harness Side)
    G00012694Courtesy of DAIMLERCHRYSLER CORP.
  2. Ensure ignition is off. Ensure battery is disconnected. Using ohmmeter, check resistance between ground and ACM connector terminal No. 4, ground circuit (Black/Pink wire). If resistance is less than 5 ohms, leave ACM connector disconnected and go to next step. If resistance is 5 ohms or more, repair open Black/Pink wire.
  3. Turn ignition on, then reconnect negative battery cable. Using a voltmeter, check voltage on ACM connector terminals No. 14, fused ignition switch start/run circuit (Dark Green/White wire) and No. 15, fused ignition switch run circuit (Tan/Light Green wire). If voltage is more than 10 volts on both circuits, leave ACM connector disconnected and go to next step. If voltage is 10 volts or less on either circuit, repair open Dark Green/White wire and/or Tan/Light Green wire. Check and replace associated fuses as necessary. See WIRING DIAGRAMS .
  4. Turn ignition off. Connect scan tool to Data Link Connector (DLC). DLC is located on bottom of instrument panel, to left of brake pedal. See Figure. Turn ignition on. Using scan tool, attempt to communicate with other modules. If scan tool does not communicate with other modules, proceed to COMPLETE PCI BUS FAILURE  test. If scan tool communicates with other modules, go to next step.
  5. Connect Scope Input Cable (CH7058) to channel one connector on scan tool. Connect Red and Black leads and Cable-to-Probe Adapter (CH7062) to scope input cable. Go to next step.
  6. Using scan tool, select DRB STANDALONE, LAB SCOPE, LIVE, then 12-VOLT SQUARE WAVE. Press F2 for scope. Press F2 again and use down arrow to set voltage range to 20 volts. Press F2 again. Go to next step.
  7. Connect Black lead to ground. Connect Red lead to ACM connector terminal No. 21, PCI bus circuit (Violet/Yellow wire). Turn ignition on. Observe voltage display on scan tool lab scope. If voltage pulses from zero to about 7.5 volts, replace ACM. See AIR BAG RESTRAINT SYSTEMS - CARS article. If voltage remains at zero volts, repair open Violet/Yellow wire. Perform BODY VERIFICATION TEST .
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