Pinpoint Tests AV: DTC U0100
Instrumentation, Message Center and Warning Chimes
Pinpoint Tests
Pinpoint Test AV: DTC U0100
Normal Operation
- DTC U0100 (Lost Communication With ECM/PCM) - sets in continuous memory in the IC if data messages received from the PCM over the High Speed Controller Area Network (HS-CAN) are missing. For a complete list of all network messages, refer to Module Communications Network Testing and Inspection.
NOTE: Once the IC sets DTC U0100, multiple gauges or indicators are likely to be inoperative in the IC. Other modules that require data from the IC all set communication DTCs and may also exhibit system function concerns.
This pinpoint test is intended to diagnose the following:
- PCM
- IC
PINPOINT TEST AV: DTC U0100
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AV1 VERIFY THAT THE SCAN TOOL CAN COMMUNICATE WITH THE PCM
- Connect the scan tool.
- Check that a vehicle session can be established using the scan tool.
- Can a vehicle session be established?
Yes
GO to AV2.
No
REFER to Module Communications Network Testing and Inspection to diagnose no communication with the PCM.
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AV2 CHECK THE IC CONTINUOUS MEMORY DTCs
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: IC Self-Test.
- Clear the DTCs. Repeat the IC self-test.
- Is DTC U0100 retrieved again?
Yes
GO to AV3.
No
The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.
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AV3 RETRIEVE THE RECORDED DTCs FROM THE IC SELF-TEST
- Check for recorded IC DTCs from the self-test.
- Is DTC B1317 or DTC B1318 recorded?
Yes
GO to Pinpoint Test AS (B1317) or GO to Pinpoint Test AT (B1318). Pinpoint Tests AS: DTC B1317 Pinpoint Tests AT: DTC B1318
No
GO to AV4.
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AV4 CHECK FOR DTC U0100 SET IN OTHER MODULES
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self-Test.
- Retrieve the continuous memory DTCs from all modules.
- Is DTC U0100 set in the ABS module or the Restraints Control Module (RCM)?
Yes
INSTALL a new PCM. REFER to Electronic Engine Controls - Service and Repair. CLEAR the DTCs. REPEAT the self-test.
No
INSTALL a new IC. REFER to Instrument Cluster (IC) Instrument Cluster (IC). TEST the system for normal operation.
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