DTC P0038: A/F/O2 Heater Control Circuit High Bank 1 Sensor 2: Notes
DTC detecting condition:
Detected when two consecutive driving cycles with fault occur.
CAUTION:
Use the check board when measuring the ECM terminal voltage and resistance. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE CHECK BOARD
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NOTE:
After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE
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Wiring diagram:
Engine Electrical System Ref. to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM .
- CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR (SHORT TO POWER SUPPLY).
- Turn the ignition switch to OFF.
- Measure the voltage between ECM connector and engine ground.
Connector and terminal.
(E158) No. 27 (+) - Engine ground (-):
Is the voltage 10 V or more?
Yes : Repair the short circuit to power supply in harness between ECM connector and rear oxygen sensor connector.
No : Go to 2.
- CHECK GROUND CIRCUIT FOR ECM (OPEN CIRCUIT).
- Disconnect the connector from ECM.
- Measure the resistance between the ECM connector and engine ground.
Connector and terminal.
(B134) No. 27 - Engine ground:
(B134) No. 40 - Engine ground:
(B134) No. 52 - Engine ground:
(B134) No. 53 - Engine ground:
(E158) No. 40 - Engine ground:
(E158) No. 53 - Engine ground:
(E159) No. 19 - Engine ground:
Is the resistance less than 5 Ω?
Yes : Repair the poor contact of ECM connector.
No : Repair the following item.
- Open circuit of harness between ECM connector and engine ground
- Poor contact of coupling connector