Pinpoint Test J: DTC U0100:00

Remote Function Actuator (RFA) Module

Pinpoint Test J: DTC U0100:00

Normal Operation
- DTC U0100:00 (Lost Communication With ECM/PCM "A": No Sub Type Information) - sets in the Remote Function Actuator (RFA) module if data messages (engine speed) received from the PCM are missing. For a complete list of all network messages, refer to Module Communications Network Testing and Inspection.

This pinpoint test is intended to diagnose the following:

- Communication network concern
- PCM
- RFA module

PINPOINT TEST J: DTC U0100:00

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J1 VERIFY 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 J2.

No
REFER to Module Communications Network Testing and Inspection, The PCM Does Not Respond To The Scan Tool.

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J2 CHECK THE RFA MODULE CONTINUOUS MEMORY DTCs

- Ignition ON.
- Enter the following diagnostic mode on the scan tool: RFA Module Self-Test.
- Clear the DTCs. Repeat the RFA module self-test.
- Is DTC U0100:00 retrieved again?

Yes
GO to J3.

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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J3 RETRIEVE THE RECORDED DTCs FROM THE RFA MODULE SELF-TEST

- Check for recorded RFA module DTCs from the self-test.
- Is DTC U3003:16 or DTC U3003:17 recorded?

Yes
For DTC U3003:16, GO to Pinpoint Test O. For DTC U3003:17, GO to Pinpoint Test P. Pinpoint Test O: DTC U3003:16 Pinpoint Test P: DTC U3003:17

No
GO to J4.

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J4 CHECK FOR DTC U0100:00 OR 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 U0100:00 or DTC U0100 set in any other module?

Yes
INSTALL a new PCM. REFER to Electronic Engine Controls Service and Repair. TEST the system for normal operation.

No
INSTALL a new RFA module. REFER to Remote Function Actuator (RFA) Module Service and Repair. TEST the system for normal operation

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