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Home >> Mazda >> 2017 >> 5 GS, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control (3 Of 3) >> DTC P2237-00: A/F Sensor Positive Current Control Circuit Open >> Diagnostic Procedure
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Diagnostic Procedure

DTC P2237:00 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA (MODE 2)
  • Perform the Freeze Frame PID Data Access Procedure. (See ON-BOARD DIAGNOSTIC TEST .)
  • Is the DTC P2237:00 on FREEZE FRAME DATA (Mode 2)?
Yes Go to the next step.
No Go to the troubleshooting procedure for DTC on FREEZE FRAME DATA (Mode 2).
(See DTC TABLE .)
2 VERIFY FREEZE FRAME DATA (MODE 2)/SNAPSHOT DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED
  • Have the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS (A/F sensor, HO2S related) been recorded?
Yes Go to the next step.
No Record the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS 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 INSPECT A/F SENSOR CONNECTOR CONDITION
  • Switch the ignition to off.
  • Disconnect the A/F 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 PCM CONNECTOR CONDITION
  • 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.
6 INSPECT A/F SENSOR POSITIVE CURRENT CONTROL CIRCUIT FOR OPEN CIRCUIT
  • Verify that the A/F sensor and PCM connectors are disconnected.
  • Inspect for continuity between A/F sensor terminal 1A (wiring harness-side) and PCM terminal 2AD (wiring harness-side).
  • Is there continuity?
Yes Go to the next step.
No Repair or replace the wiring harness for a possible open circuit, then go to Step 8.
7 INSPECT A/F SENSOR
Yes Replace the A/F sensor, then go to the next step.
(See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION .)
No Go to the next step.
8 VERIFY DTC TROUBLESHOOTING COMPLETED
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE .)
  • Perform the KOEO or KOER self test or Drive Mode 03 (EGR System, A/F Sensor Heater, HO2S Heater, A/F Sensor, HO2S and TWC Repair Verification Drive Mode). (See KOEO/KOER SELF TEST .) (See OBD-II DRIVE MODE .)
  • Is the PENDING CODE for this DTC present?
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 .)
No DTC troubleshooting completed.