DTC DETECTION LOGIC
DTC No. | Trouble diagnosis name | DTC detecting condition | Possible cause |
P0031 | Air fuel ratio (A/F) sensor 1 heater control circuit low | The current amperage in the A/F sensor 1 heater circuit is out
of the normal range.
(An excessively low voltage signal is sent to ECM through the A/F sensor 1 heater.) |
|
P0032 | Air fuel ratio (A/F) sensor 1 heater control circuit high | The current amperage in the A/F sensor 1 heater circuit is out
of the normal range.
(An excessively high voltage signal is sent to ECM through the A/F sensor 1 heater.) |
|
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
TESTING CONDITION: Before performing the following procedure, confirm that battery voltage is between 10 V and 16 V at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
Is 1st trip DTC detected?
YES >> Go to EC, "Diagnosis Procedure".
NG >> INSPECTION END
1.CHECK GROUND CONNECTION
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace ground connection.
2.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
>> Repair or replace harness or connectors.
4.CHECK A/F SENSOR 1 HEATER OUTPUT SIGNAL CIRCUIT
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
5.CHECK A/F SENSOR 1 HEATER
Refer to EC, "Component Inspection".
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 6.
6.REPLACE AIR FUEL RATIO (A/F) SENSOR 1
Replace malfunctioning air fuel ratio (A/F) sensor 1. Refer to EM, "Exploded View".
CAUTION:
>> INSPECTION END
7.CHECK INTERMITTENT INCIDENT
Perform GI, "Intermittent Incident".
>> Repair or replace.
1.CHECK AIR FUEL RATIO (A/F) SENSOR 1
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 2.
2.REPLACE AIR FUEL RATIO (A/F) SENSOR 1
Replace malfunctioning air fuel ratio (A/F) sensor 1. Refer to EM, "Exploded View".
CAUTION:
>> INSPECTION END
Power supply and ground circuit
Diagnosis Procedure
1.CHECK GROUND CONNECTION
Turn ignition switch OFF.
Check ground connection E. Refer to Ground Inspection in GI, "Circuit
Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace ground connection.
2.CHECK ECM G ...
U0073 Communication bus A off
Description
CAN (Controller Area Network) is a serial communication line for real-time
application. It is an on-vehicle multiplex
communication line with high data communication speed and excellent malfunction
detection ability.
Many electronic control units are equipped onto a vehicle, an ...