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Home >> Mazda >> 2016 >> 3 Sport, 4D Hatchback, Automatic Trans >> Repair and Diagnosis >> Transmission >> Transmission Control Systems >> On-Board Diagnostics - Transmission Control System >> DTC P0843-00: Oil Pressure Switch No. 1 Is Built Into Oil Pressure Switch B. >> Diagnostic Procedure
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Diagnostic Procedure

STEP INSPECTION ACTION
1 VERIFY DTC OUTPUT STATUS 
  • Is the DTC P1738:00 also present?
 Yes Go to the applicable DTC inspection.
(Refer to DTC P1738:00 [FW6A-EL] .)
No Go to the next step.
2 VERIFY FREEZE FRAME DATA/SNAPSHOT DATA HAS BEEN RECORDED 
  • Has the freeze frame data/snapshot data been recorded on the repair order?
 Yes Go to the next step.
No Record the freeze frame data/snapshot data on the repair order, then go to the next step.
3 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.
4 VERIFY THAT DTC IS PRESENT 
 Yes Go to the next step.
No DTC troubleshooting completed.
5 INSPECT ATF LEVEL 
 Yes Adjust the ATF level to the specification, then go to Step 7.
(Refer to AUTOMATIC TRANSAXLE FLUID (ATF) REPLACEMENT [FW6A-EL] .)
No DTC P0843:00 and P0878:00 are displayed in Step 4:
  • Refer to the wiring diagram and verify whether or not there is a common connector between TCM and oil pressure switch 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 malfunction.
    • Repair or replace the malfunctioning part.

      If there is no common connector: 

    • Repair or replace the wiring harness.
  • Go to Step 7.

Only DTC P0843:00 is displayed in Step 4:
  • Go to the next step.
6 INSPECT OIL PRESSURE SWITCH A CONNECTOR AND OIL PRESSURE SWITCH NO. 1 CIRCUIT 
  • Visually inspect for poor connection and open circuit.
  • Is there any malfunction?
 Yes Refer to the wiring diagram and verify whether or not there is a common connector between TCM and oil pressure switch 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 malfunction.
  • Repair or replace the malfunctioning part.

    If there is no common connector: 

  • Repair or replace the wiring harness.

Go to the next step.
No Replace the oil pressure switch A, then go to the next step.
(Refer to OIL PRESSURE SWITCH REMOVAL/INSTALLATION [FW6A-EL] .)
7 PERFORM ON-BOARD DIAGNOSTIC TEST 
  • Perform the following procedure to ensure that the DTC has been resolved:
    • Start the engine.
    • Verify that the ATF temperature is 55 °C {131 °F} or more. 
  • Perform the on-board diagnostic test.

    (Refer to ON-BOARD DIAGNOSTIC TEST MODE [FW6A-EL] .)

  • Are any DTCs present?
 Yes ATF amount in Step 5 is correct

ATF amount adjusted in Step 5:
No Drive the vehicle to check it, and if there is no problem then the DTC troubleshooting is complete.
8 RE-PERFORM ON-BOARD DIAGNOSTIC TEST 
  • Perform the following procedure to ensure that the DTC has been resolved:
    • Start the engine.
    • Verify that the ATF temperature is 55 °C {131 °F} or more. 
  • Perform the on-board diagnostic test.

    (Refer to ON-BOARD DIAGNOSTIC TEST MODE [FW6A-EL] .)

  • Are any DTCs present?
 Yes Go to the applicable DTC inspection.
(Refer to ON-BOARD DIAGNOSTIC SYSTEM DTC TABLE [FW6A-EL] .)
No DTC troubleshooting completed.
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