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DTC P0032

DTC P0032

A/F sensor heater control circuit high input

DETECTION CONDITION

The input voltage to the A/F sensor heater drive terminal in the PCM is at the set value or more for 1 s or more even though the A/F sensor heater is duty-controlled at 10% or more by the PCM.
If the current flowing to the A/F sensor heater circuit in the PCM is high when the A/F sensor heater is off, the PCM detects DTC P0032.

Diagnostic support note

This is a continuous monitor (A/F sensor heater, HO2S heater).
The MIL illuminates if the PCM detects the above malfunction 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 condition during the first drive cycle.
FREEZE FRAME DATA (Mode 2/Mode 12) is available.
The DTC is stored in the PCM memory.

POSSIBLE CAUSE

A/F sensor connector or terminals malfunction
A/F sensor heater malfunction
PCM connector or terminals malfunction
Short to power supply in wiring harness between A/F sensor terminal D and PCM terminal 2BG
PCM malfunction

G07878093

DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA (MODE 12) AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED Have the FREEZE FRAME DATA (Mode 12) and DIAGNOSTIC MONITORING TEST RESULTS (A/F sensor heater, HO2S heater related) been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA (Mode 12) and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then 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.
2		No	Go to the next step.
3	INSPECT A/F SENSOR CONNECTOR FOR POOR CONNECTION Turn the ignition switch 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 connector and/or terminals, then go to Step 7.
3		No	Go to the next step.
4	INSPECT A/F SENSOR HEATER Inspect the A/F sensor heater. (See AIR FUEL RATIO (A/F) SENSOR INSPECTION . Is there any malfunction?	Yes	Replace the A/F sensor, then go to Step 7. (See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION ).
4		No	Go to the next step.
5	INSPECT PCM CONNECTOR FOR POOR CONNECTION Turn the ignition switch 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 connector and/or terminals, then go to Step 7.
5		No	Go to the next step.
6	INSPECT A/F SENSOR HEATER CONTROL CIRCUIT FOR SHORT TO POWER SUPPLY A/F sensor and PCM connectors are disconnected. Turn the ignition switch to the ON position (engine off). Measure the voltage between A/F sensor terminal D (wiring harness-side) and body ground. Is the voltage B+?	Yes	Repair or replace the wiring harness for a possible short to power supply, then go to the next step.
6		No	Go to the next step.
7	VERIFY TROUBLESHOOTING OF DTC P0032 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. (See KOEO/KOER SELF TEST ). Is the PENDING CODE same as the DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION ).
7		No	Go to the next step.
8	VERIFY AFTER REPAIR PROCEDURE Perform the "AFTER REPAIR PROCEDURE ". (See AFTER REPAIR PROCEDURE ). Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE ).
8		No	DTC troubleshooting completed.