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Home >> Mazda >> 2019 >> CX-9 Signature >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control System (3 Of 3) >> DTC U1100-00: Lin Communication - Communication Error To Engine Oil Level Sensor >> Diagnostic Procedure
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Diagnostic Procedure

DTC U1100:00 (PCM, SKYACTIV-G 2.5T) DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 RECORD VEHICLE STATUS AT TIME OF DTC DETECTION TO UTILIZE WITH REPEATABILITY VERIFICATION 
NOTE:
  • Recording can be facilitated using the screen capture function of the PC.
  • Record the snapshot data on the repair order.
 - Go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Service Bulletins and/or on-line repair information availability.
  • Is any related repair information available?
 Yes Perform repair or diagnosis according to the available repair information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
3 VERIFY RELATED PENDING CODE AND/OR DTC  Yes Go to the applicable PENDING CODE or DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.5T)] .)
No Go to the next step.
4 INSPECT ENGINE OIL LEVEL SENSOR CONNECTOR CONDITION 
  • Switch the ignition off.
  • Disconnect the engine oil level sensor connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 8.
No Go to the next step.
5 INSPECT ENGINE OIL LEVEL SENSOR POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT 
  • Verify that the engine oil level sensor connector is disconnected.
  • Switch the ignition ON (engine off).
    NOTE:
    • Another DTC may be stored by the PCM detecting an open circuit.
  • Measure the voltage at the engine oil level sensor terminal A (wiring harness-side).
  • Is the voltage B+?
 Yes Go to the next step.
No Inspect the ENGINE3 15 A fuse.
  • If the fuse is blown:
    • Refer to the wiring diagram and verify whether or not there is a common connector between ENGINE3 15 A fuse and engine oil level sensor terminal A.

      If there is a common connector: 

      • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
      • Repair or replace the malfunctioning part.

      If there is no common connector: 

      • Repair or replace the wiring harness which has a short to ground.
      • Replace the fuse.
  • If the fuse is damaged:
    • Replace the fuse.
  • If the fuse is normal:
    • Refer to the wiring diagram and verify whether or not there is a common connector between main relay terminal C and engine oil level sensor terminal A.

      If there is a common connector: 

      • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
      • Repair or replace the malfunctioning part.

      If there is no common connector: 

      • Repair or replace the wiring harness which has an open circuit.

Go to Step 8.
6 INSPECT PCM CONNECTOR CONDITION 
  • Switch the ignition off.
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 8.
No Go to the next step.
7 INSPECT ENGINE OIL LEVEL SENSOR  Yes Replace the engine oil level sensor, then go to the next step.
(See ENGINE OIL LEVEL SENSOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)
No Go to the next step.
8 VERIFY DTC TROUBLESHOOTING COMPLETED  Yes Repeat the inspection from Step 1.
Go to the next step.
No Go to the next step.
9 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.5T)] .)
No DTC troubleshooting completed.
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