Pinpoint Test AH: DTC U0164 Or DTC U0164:00
Information and Entertainment System
Pinpoint Tests
Pinpoint Test AH: DTC U0164 Or DTC U0164:00
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
Some audio system modules receive network messages from the HVAC module via the Medium Speed Controller Area Network (MS-CAN). The following information is included in the messages:
- HVAC indication status
- Outside temperature
As more than one module receives these messages, all modules receiving a particular message should exhibit a symptom if the message is missing.
- DTC U0164 (Lost Communication With HVAC Control Module (EATC)) - set by the non-navigation (Fusion,
Milan) Front Controls Interface Module (FCIM) or the Front Display Interface Module (FDIM) when network messages are missing from the HVAC module for greater than 5 seconds with the ignition in RUN.
- DTC U0164:00 (Lost Communication With HVAC Control Module: No Sub Type Information) - set by the navigation Audio Control Module (ACM) when network messages are missing from the HVAC module for greater than 5 seconds with the ignition in RUN.
This pinpoint test is intended to diagnose the following:
- Communication network concern
- Audio system concern
- HVAC module
PINPOINT TEST AH: DTC U0164 OR DTC U0164:00
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AH1 CHECK FOR LOST COMMUNICATION DTCs
- Ignition ON.
- Clear continuous DTCs from all modules.
- Ignition OFF.
- Ignition ON.
- Wait at least 10 seconds.
- Retrieve all continuous DTCs from all modules.
- Is DTC U0164 or DTC U0164:00 set in any audio system module?
Yes
GO to AH2.
No
The system is operating correctly at this time. The DTC may have been set due to an intermittent fault in the network wiring.
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AH2 CHECK FOR BATTERY VOLTAGE OUT-OF-RANGE DTCs
- Carry out the self-test for the following modules:
- ACM
- FCIM
- FDIM
- HVAC module
- Is DTC B1317, B1318, U3003:16, or U3003:17 recorded in any module?
Yes
For an audio system module, REFER to DTC Charts. [1][2]Diagnostic Trouble Code Descriptions
For the HVAC module, REFER to Heating and Air Conditioning.
No
GO to AH3.
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AH3 CHECK FOR DTC U0164 OR DTC U0164:00 SET IN MULTIPLE MODULES
- Review the recorded results from the self-test.
- Is DTC U0164 or DTC U0164:00 set in more than one audio system module?
Yes
GO to AH4.
No
If there is an observable symptom, GO to Symptom Chart - General Audio System to diagnose the observed symptom. Symptom Chart - General Audio System
If there is no observable symptom, CHECK the MS-CAN wiring between the HVAC module and the module in question for an intermittent fault.
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AH4 CHECK FOR CORRECT HVAC MODULE OPERATION
- Disconnect all the HVAC module connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the HVAC module connectors and make sure they seat correctly.
- Is the concern still present?
Yes
INSTALL a new HVAC module. CLEAR all continuous DTCs. 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 all continuous DTCs. REPEAT the self-test for the module(s) that set DTC U0164 or DTC U0164:00.
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