F 550 4WD Super Duty V10-6.8L (2009)
Pinpoint Tests
Pinpoint Test K: The Audio Control Module (ACM) Does Not Respond To The Scan Tool
Refer to Wiring Diagrams Set 14 (Escape/Mariner, Escape Hybrid/Mariner Hybrid), Module Communications Network for schematic and connector
information. See: Diagrams/Electrical Diagrams/Diagrams By Number
Refer to Wiring Diagrams Set 130 (Escape/Mariner, Escape Hybrid/Mariner Hybrid), Audio System/Navigation for schematic and connector
information. See: Diagrams/Electrical Diagrams/Diagrams By Number
Normal Operation
The Audio Control Module (ACM) communicates with the scan tool through the Medium Speed Controller Area Network (MS-CAN). Circuits VDB06
(GY/OG) (MS-CAN +) and VDB07 (VT/OG) (MS-CAN -) provide the network connection to the ACM. Voltage for the ACM is provided by circuit
SBP39 (WH/RD). Ground is provided by circuit GD114 (BK/BU).
This pinpoint test is intended to diagnose the following:
-
Fuse
-
Wiring, terminals or connectors
-
ACM
PINPOINT TEST K: THE ACM DOES NOT RESPOND TO THE SCAN TOOL
NOTICE: 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.
-------------------------------------------------
K1 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 SPB39 (WH/RD), harness side and ground.
-
Is the voltage greater than 10 volts?
Yes
GO to K2.
No
VERIFY the Smart Junction Box (SJB) fuse 39 (20A) is OK. If OK, REPAIR the circuit in question. If not OK, REFER to the Wiring Diagrams to
identify the possible causes of the circuit short. CLEAR the DTCs. REPEAT the network test with the scan tool.
-------------------------------------------------
K2 CHECK THE ACM GROUND CIRCUIT FOR AN OPEN
-
Ignition OFF.
-
Disconnect: Negative Battery Cable.
-
Measure the resistance between the ACM C240a-13, circuit GD114 (BK/BU), harness side and ground.
