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Pinpoint Test P: The ACM Does Not Respond To The Scan Tool

WARNING: This page is about a different car, the 2010 Mercury Mariner and 2010 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to BATTERY, MOUNTING AND CABLES .
  1. P1 CHECK THE ACM VOLTAGE SUPPLY CIRCUIT FOR AN OPEN 
    • Ignition OFF.
    • Disconnect: ACM  C240a.
    • Ignition ON.
    • Measure the voltage between the ACM  C240a-1, circuit SBP39 (WH/RD), harness side and ground.
      Fig 1: Measuring Voltage Between ACM C240A-1, Circuit SBP39 (WH/RD), Harness Side And Ground
      G06099337Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 
    • Yes:  GO to P2  .
    • No:  VERIFY the Smart Junction Box (SJB) fuse 39 (20A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the appropriate SYSTEM WIRING DIAGRAMS article to identify the possible causes of the circuit short. CLEAR the DTCs. REPEAT the network test with the scan tool.
  2. P2 CHECK THE ACM GROUND CIRCUIT FOR AN OPEN 
    • Ignition OFF.
    • Disconnect: Negative Battery Cable.
    • Measure the resistance between the ACM  C240a-13, circuit GD115 (BK/GY), harness side and ground.
      Fig 2: Measuring Resistance Between ACM C240A-13, Circuit GD115 (BK/GY), Harness Side And Ground
      G06099338Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    • Yes:  GO to P3  .
    • No:  REPAIR the circuit. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
  3. P3 CHECK THE MS-CAN CIRCUITS BETWEEN THE ACM AND THE DLC FOR AN OPEN 
    • Disconnect: ACM  C240b.
    • Measure the resistance between the ACM  C240b-15, circuit VDB06 (GY/OG), harness side and the Data Link Connector (DLC) C251-3, circuit VDB06 (GY/OG), harness side.
      Fig 3: Measuring Resistance Between ACM C240B-15, Circuit VDB06 (GY/OG) And DLC C251-3, Circuit VDB06 (GY/OG), Harness Side
      G06065473Courtesy of FORD MOTOR CO.
    • Measure the resistance between the ACM  C240b-16, circuit VDB07 (VT/OG), harness side and the DLC  C251-11, circuit VDB07 (VT/OG), harness side.
      Fig 4: Measuring Resistance Between ACM C240B-16, Circuit VDB07 (VT/OG) And DLC C251-11, Circuit VDB07 (VT/OG), Harness Side
      G06065474Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    • Yes:  CONNECT the negative battery cable. GO to P4  .
    • No:  REPAIR the circuit in question. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
  4. P4 CHECK FOR CORRECT ACM OPERATION 
    • Disconnect all the ACM  connectors.
    • Check for:
      • corrosion
      • damaged pins
      • pushed-out pins
    • Connect all the ACM  connectors and make sure they seat correctly.
    • Operate the system and verify the concern is still present.
    • Is the concern still present? 
    • Yes:  INSTALL a new ACM  . REFER to INFORMATION AND ENTERTAINMENT SYSTEMS . CLEAR the DTCs. REPEAT the network test with the scan tool.
    • No:  The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
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