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

WARNING: This page is about a different car, the 2013 Ford Mustang. 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 results in false resistance readings. Refer to BATTERY, MOUNTING AND CABLES .

I1 CHECK THE ACM VOLTAGE SUPPLY CIRCUITS FOR AN OPEN
- Ignition OFF.
- Disconnect: ACM C290D.
- Ignition ON.
- Measure the voltage between the ACM C290D-1, circuit SBP39 (WH/RD), harness side and ground.
  
  Fig 1: Measuring Voltage Between ACM C290D-1, Circuit SBP39 (WH/RD) And Ground
  Courtesy of FORD MOTOR CO.
- Are the voltages greater than 10 volts?
- Yes : GO to I2.
- No : VERIFY the SJB fuse 39 (20A) is OK. If OK, REPAIR the circuit in question. If not OK, REFER to the SYSTEM WIRING DIAGRAMS to identify the possible causes of the circuit short. CLEAR the DTCs. REPEAT the network test with the scan tool.
I2 CHECK THE ACM GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Measure the resistance between the ACM C290D-13, circuit GD115 (BK/GY), harness side and ground.
  
  Fig 2: Measuring Resistance Between ACM C290D-13, Circuit GD115 (BK/GY) And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : GO to I3.
- No : REPAIR the circuit. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
I3 CHECK THE MS-CAN CIRCUITS BETWEEN THE ACM AND THE DLC FOR AN OPEN
- Disconnect: ACM C290A.
- Measure the resistance between the ACM C290A-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 C290A-15, Circuit VDB06 (GY/OG) And Data Link Connector (DLC) C251-3
  Courtesy of FORD MOTOR CO.
- Measure the resistance between the ACM C290A-16, circuit VDB07 (VT/OG), harness side and the DLC C251-11, circuit VDB07 (VT/OG), harness side.
  
  Fig 4: Measuring Resistance Between ACM C290A-16, Circuit VDB07 (VT/OG) And DLC C251-11
  Courtesy of FORD MOTOR CO.
- Are the resistances less than 5 ohms?
- Yes : CONNECT the negative battery cable. GO to I4.
- No : REPAIR the circuit in question. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
I4 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 . TEST the system for normal operation.
- No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the network test with the scan tool.