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ACIS Circuit

CAUTION: If ECM replacement is instructed in following testing, always ensure ECM harness connector and ground circuit are okay. If either are suspect, repair and repeat testing to confirm ECM malfunction.
  1. Check ACIS Vacuum Switching Valve (VSV). See ACIS VACUUM SWITCHING VALVE (VSV) . If VSV is okay, pull back the right front floor mat. Remove ECM protective cover. Connect Check Harness (SST 09990-01000) between ECM and harness. See USING CHECK HARNESS under INTRODUCTION. Turn ignition on.
  2. Measure voltage between chassis ground and terminal No. 39 (Green/Red wire) at ECM "B" connector. See Figure.
  3. If battery voltage is present, check for faulty vacuum tank or hoses. See ACIS VACUUM TANK . If battery voltage is not present, check for open or shorted circuit between EFI main relay and ECM. If circuit is okay, replace ECM.
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