P0053

DTC P0053: Cylinder 1, 4 Heated Oxygen Sensor Heater (front) Resistance


















CIRCUIT OPERATION

- Power is supplied from the MFI relay (terminal No. 4) to the cylinder 1, 4 heated oxygen sensor (front) heater.
- The ECM [M/T] or the PCM [A/T] (terminal No. 126) controls continuity to the cylinder 1, 4 heated oxygen sensor (front) heater by turning the power transistor in the ECM [M/T] or the PCM [A/T] "ON" and "OFF".

TECHNICAL DESCRIPTION

- The ECM [M/T] or the PCM [A/T] checks whether the heater current is within a specified range when the heater is energized.

DESCRIPTIONS OF MONITOR METHODS

Cylinder 1, 4 heated oxygen sensor heater (front) current is out of specified range.

MONITOR EXECUTION

Continuous

MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)

Other Monitor (There is no temporary DTC stored in memory for the item monitored below)

- Not applicable
Sensor (The sensor below is determined to be normal)

- Not applicable

DTC SET CONDITIONS

Logic Flow Chart






Check Conditions

- More than 60 seconds have passed since the engine starting sequence was completed.
- While the cylinder 1, 4 heated oxygen sensor heater is on.
- Battery positive voltage is between 11 and 16.5 volts.
- Intake air temperature is more than -10°C (14°F).
- On duty cycle of the cylinder 1, 4 heated oxygen sensor heater is between 3 and 97 percent.
Judgement Criterion

- The cylinder 1, 4 heated oxygen sensor heater current has continued to be lower than average 0.6 ampere for 10 seconds.

OBD-II DRIVE CYCLE PATTERN

Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 2 Monitors, Trips, Drive Cycles and Readiness Codes .

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)

- Harness damage in cylinder 1, 4 heated oxygen sensor (front) heater circuit or connector damage.
- Cylinder 1, 4 heated oxygen sensor (front) heater failed.
- ECM failed.[ M/T]
- PCM failed.[ A/T]

DIAGNOSIS

Required Special Tools:

- MB991316: Test Harness

STEP 1. Check harness connector B-36 at the cylinder 1, 4 heated oxygen sensor (front) for damage.





Q. Is the harness connector in good condition?

YES Go to Step 2.

NO Repair or replace it. Harness Connector Inspection.
Then go to Step 8.

STEP 2. Check the cylinder 1, 4 heated oxygen sensor (front).





(1)Disconnect cylinder 1, 4 heated oxygen sensor (front) connector B-36 and connect test harness special tool, MB991316, to the connector on the cylinder 1, 4 heated oxygen (front) sensor side.





(2)Measure the resistance between heated oxygen sensor connector terminal No. 1 (red clip) and terminal No. 3 (blue clip).
Standard value: 4.5 - 8.0ohms [at 20°C (68°F)]

Q. Is the measured resistance between 4.5 and 8.0 ohms [at 20°C (68°F)]?

YES Go to Step 3.

NO Replace the cylinder 1, 4 heated oxygen sensor (front). Then go to Step 8.

STEP 3. Check harness connector B-16X at the MFI relay for damage.





Q. Is the harness connector in good condition?

YES Go to Step 4.

NO Repair or replace it. Harness Connector Inspection.
Then go to Step 8.

STEP 4. Check for harness damage between MFI relay connector B-16X (terminal No. 4) and cylinder 1, 4 heated oxygen sensor (front) connector B-36 (terminal No. 1).









Q. Is the harness wire in good condition?

YES Go to Step 5.

NO Repair it. Then go to Step 8.

STEP 5. Check harness connector B-22 at ECM [M/T] or PCM [A/T] for damage.





Q. Is the harness connector in good condition?

YES Go to Step 6.

NO Repair or replace it. Harness Connector Inspection.
Then go to Step 8.

STEP 6. Check for harness damage between cylinder 1, 4 heated oxygen sensor (front) connector B-36 (terminal No. 3) and ECM [M/T] or PCM [A/T] connector B-22 (terminal No. 126).









Q. Is the harness wire in good condition?

YES Go to Step 7.

NO Repair it. Then go to Step 8.

STEP 7. Check the trouble symptoms.

(1)Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 2 Monitors, Trips, Drive Cycles and Readiness Codes.

(2)Check the diagnostic trouble code (DTC).

Q. Is DTC P0053 set?

YES Replace the ECM or the PCM. When the ECM or the PCM is replaced, register the encrypted code. Immobilizer System.
Then go to Step 8.
NO It can be assumed that this malfunction is intermittent. How to Cope With Intermittent Malfunctions.
STEP 8. Test the OBD-II drive cycle.

(1)Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 2 Monitors, Trips, Drive Cycles and Readiness Codes.

(2)Check the diagnostic trouble code (DTC).

Q. Is DTC P0053 set?

YES Retry the troubleshooting.
NO The inspection is complete.