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DTC P2237 [L3 Turbo]

id0102b7813100

DTC P2237 | A/F sensor positive current control circuit open
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DETECTION CONDITION | • The PCM monitors the A/F sensor positive current control circuit voltage. If the voltage does not change with the PCM control value while the engine is running, the PCM determines that the A/F sensor positive current control circuit is open. Diagnostic support note • This is a continuous monitor. (A/F sensor , HO2S) • MIL illuminates if the PCM detects the above malfunctioning condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM. • PENDING CODE is available if the PCM detects the above malfunction conditions during the first drive cycle. • FREEZE FRAME DATA is available. • DTCs are stored in the PCM memory.
POSSIBLE CAUSE | • A/F sensor malfunction • Connector or terminal malfunction • Open circuit between PCM terminal 2D and A/F sensor terminal 1A • PCM malfunction

Diagnostic procedure

STEP | INSPECTION | ACTION
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1 | VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAS BEEN RECORDED • Has FREEZE FRAME DATA been recorded? | Yes | Go to the next step.
No | Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2 | VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Verify related Service Information availability. • Is any related Service Information available? | Yes | Perform repair or diagnosis according to the available Service information. If the vehicle is not repaired, go to the next step.
No | Go to the next step.
3 | IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA • Is DTC P2237 on FREEZE FRAME DATA? | Yes | Go to the next step.
No | Go to troubleshooting for DTC on FREEZE FRAME DATA. (SeeDTC TABLE [L3 Turbo].)
4 | INSPECT A/F SENSOR CONNECTOR FOR POOR CONNECTION • Turn the ignition switch to off. • Disconnect the A/F sensor connector. • Inspect for poor connection (such as damaged/ pulled-out pins, and corrosion). • Is there any malfunction? | Yes | Repair or replace the terminal, then go to Step.
No | Go to the next step.
5 | INSPECT PCM CONNECTOR FOR POOR CONNECTION • Turn the ignition switch to off. • Disconnect the PCM connector. • Inspect for poor connection (such as damaged/ pulled-out pins, and corrosion). • Is there any malfunction? | Yes | Repair or replace the terminal, then go to Step.
No | Go to the next step.
6 | INSPECT A/F SENSOR POSITIVE CURRENT CIRCUIT FOR OPEN AT PCM - A/F SENSOR • A/F sensor and PCM connectors disconnected. • Verify the continuity between PCM terminal 2D and A/F sensor terminal 1A. • Is there continuity? | Yes | Replace the A/F sensor, then go to the next step.
No | Repair or replace the wiring harness for an open, then go to the next step.
7 | VERIFY TROUBLESHOOTING OF DTC P2237 COMPLETED • Make sure to reconnect all disconnected connectors. • Clear the DTC from the PCM memory using the WDS or equivalent. • Perform the A/F sensor heater, HO2S heater, A/F sensor, HO2S and TWC Repair Verification Drive Mode. (SeeOBD DRIVE MODE [L3 Turbo].) • Is the PENDING CODE same DTC present? | Yes | Replace the PCM, then go to the next step. (SeePCM REMOVAL/INSTALLATION [L3 Turbo].)
No | Go to the next step.
8 | VERIFY AFTER REPAIR PROCEDURE • Perform the "After Repair Procedure". (SeeAFTER REPAIR PROCEDURE [L3 Turbo].) • Are any DTCs present? | Yes | Go to the applicable DTC inspection. (SeeDTC TABLE [L3 Turbo].)
No | Troubleshooting completed.