Pinpoint Tests AJ: DTC U0164

Instrumentation, Message Center and Warning Chimes

Pinpoint Tests

Pinpoint Test AJ: DTC U0164

Normal Operation
- DTC U0164 (Lost Communication With HVAC Control Module (EATC)) - sets in the Instrument Cluster (IC) if data messages received from the HVAC module over the MS-CAN are missing.

This pinpoint test is intended to diagnose the following:

- HVAC module
- IC



PINPOINT TEST AJ: DTC U0164

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AJ1 VERIFY CUSTOMER CONCERN


- Ignition ON.
- Verify that there is an observable symptom present.
- Is an observable symptom present?

Yes
GO to AJ2.

No
The system is operating normally at this time. The DTC may have been set due to high network traffic or intermittent fault condition.

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AJ2 CHECK THE COMMUNICATION NETWORK


- Enter the following diagnostic mode on the scan tool: Network Test.
- Carry out the network test.
- Does the HVAC module pass the network test?

Yes
GO to AJ3.

No
REFER to Information Bus.

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AJ3 RETRIEVE THE RECORDED DTCs FROM THE CONTINUOUS AND ON-DEMAND IC SELF-TESTS


- Check for recorded IC DTCs from the continuous and on-demand self-tests.
- Is DTC B1317 or B1318 recorded?

Yes
For DTC B1317, Go To Pinpoint Test AB. Pinpoint Tests AB: DTC B1317

For DTC B1318, Go To Pinpoint Test AC. Pinpoint Tests AC: DTC B1318

No
GO to AJ4.

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AJ4 RECHECK THE IC CONTINUOUS MEMORY DTCs


NOTE: If new modules were installed prior to the DTC being set, the module configuration may be incorrectly set during Programmable Module Installation (PMI) may not have been carried out.

- Enter the following diagnostic mode on the scan tool: IC Self-Test.
- Clear the DTCs. Repeat the IC self-test.
- Is DTC U0164 still present?

Yes
INSTALL a new HVAC module. TEST the system for normal operation. Repeat the self-test.

If DTC U0164 is still present, INSTALL a new IC. REFER to Instrument Cluster (IC) Instrument Cluster (IC). TEST the system for normal operation.

No
The system is operating correctly at this time. The DTC may have been set due to high network traffic or intermittent fault condition.

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