Pinpoint Test Ai: DTC U0100:00

WARNING: This page is about a different car, the 2010 Mercury Mariner and 2010 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

AI1 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 U0100 or DTC U0100:00 set in any modules?
- Yes: GO to AI2 .
- No: The system is operating correctly at this time. The DTC may have been set due to an intermittent fault in the network wiring.
AI2 CHECK FOR BATTERY VOLTAGE OUT-OF-RANGE DTCs
- Carry out the self-test for the following modules:
  - APIM
  - PCM
  - Instrument Cluster (IC)
- Is DTC B1317, B1318, U3003:16 or U3003:17 recorded in any module?
- Yes: For the APIM , REFER to DTC CHARTS .
  For all other modules, REFER to the Diagnostic Trouble Code (DTC) Chart in MULTIFUNCTION ELECTRONIC MODULES .
- No: GO to AI3 .
AI3 CHECK FOR DTC U0100 OR DTC U0100:00 SET IN MULTIPLE MODULES
- Review the recorded results from the self-test.
- Is DTC U0100 or DTC U0100:00 set in more than one module?
- Yes: GO to AI4 .
- No: If there is an observable symptom, GO to SYMPTOM CHART - GENERAL AUDIO SYSTEM to diagnose the observed symptom.
  If there is no observable symptom, CHECK the wiring between the APIM and the PCM for an intermittent fault.
AI4 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect all the PCM connectors and make sure they seat correctly.
- Is the concern still present?
- Yes: INSTALL a new PCM. Refer to the ELECTRONIC ENGINE CONTROLS - 2.5L -- GASOLINE MODELS for the procedure. CLEAR all continuous DTCs. REPEAT the APIM self-test.
- 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 APIM self-test.