Pinpoint Test AO: DTC B1318 Or DTC U3003:16 (Audio Control Module (ACM))
Information and Entertainment System
Pinpoint Tests
Pinpoint Test AO: DTC B1318 Or DTC U3003:16 (Audio Control Module (ACM))
Refer to Wiring Diagram Set 130 (Fusion/Milan/MKZ, Fusion Hybrid/Milan Hybrid), Audio System/Navigation for schematic and connector information. Diagrams By Number
Normal Operation
- DTC B1318 (Battery Voltage Low) - set by the non-navigation (Fusion, Milan) Audio Control Module (ACM) as a continuous or on-demand DTC when the supply voltage falls below 10 volts for at least 10 seconds during normal operation.
- DTC U3003:16 (Battery Voltage: Circuit Voltage Below Threshold) - set by the non-navigation (MKZ) or navigation (all) ACM as a continuous or on-demand DTC when the supply voltage falls below 10 volts for at least 10 seconds during normal operation, or for greater than 250 milliseconds during the self-test.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- High circuit resistance
- ACM
PINPOINT TEST AO: DTC B1318 Or DTC U3003:16 (ACM)
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. Refer to Battery.
-------------------------------------------------
AO1 RECHECK THE ACM DTCs
- Clear the ACM DTCs.
- Ignition OFF.
- Ignition ON.
- Wait 10 seconds.
- Repeat the ACM self-test.
- Is DTC B1318 or DTC U3003:16 still present?
Yes
GO to AO2.
No
The system is operating correctly at this time. The DTC may have set due to a previous low battery voltage condition.
-------------------------------------------------
AO2 CHECK FOR CHARGING SYSTEM DTCs IN THE PCM
- Retrieve the continuous memory DTCs from all modules.
- Is DTC P0620, P0622, P0625, P0626, or P065B set in the PCM?
Yes
REFER to Charging System.
No
GO to AO3.
-------------------------------------------------
AO3 CHECK THE BATTERY CONDITION AND STATE OF CHARGE
- Check the battery condition and verify that the battery is fully charged. Refer to Battery.
- Is the battery OK and fully charged?
Yes
GO to AO4.
No
REFER to Battery.
-------------------------------------------------
AO4 CHECK THE ACM VOLTAGE SUPPLY
- Ignition OFF.
- Measure and record the voltage at the battery.
- Disconnect: ACM C240a .
- Ignition ON.
- Measure the voltage between the ACM C240a-1, circuit SBP39 (WH/RD), harness side and ground.
- Is the voltage within 0.2 volt of the recorded battery voltage?
Yes
GO to AO5.
No
REPAIR the circuit for high resistance. CLEAR the DTCs. REPEAT the self-test.
-------------------------------------------------
AO5 CHECK THE ACM GROUND CIRCUIT FOR CONTINUITY
- Ignition OFF.
- Disconnect: Negative Battery Cable .
- Measure the resistance between the ACM C240a-13, circuit GD114 (BK/BU), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to AO6.
No
REPAIR the circuit for high resistance. CLEAR the DTCs. REPEAT the self-test.
-------------------------------------------------
AO6 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.
- Is the concern still present?
Yes
INSTALL a new ACM. REFER to Audio Control Module (ACM) - Fusion, Milan Audio Control Module (ACM) or Audio Control Module (ACM) - MKZ Audio Control Module (ACM). 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.
-------------------------------------------------