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DTC P0133 O2 SENSOR CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 1)

DTC P0133 O 2 SENSOR CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 1)

OUTLINE OF DIAGNOSIS

Detect time-lag of front oxygen (A/F) sensor response. Front oxygen (A/F) sensor cover has some ventilation holes for exhaust gas. Clogged ventilation holes are diagnosed. When the holes are clogged, the A/F output variation becomes slow comparing with the actual A/F variation because oxygen which reaches the zirconia layer is insufficient. Therefore, if the cover has clogged holes, the rich to lean judgment in ECM is delayed when the change from rich to lean is caused.


(1)

Cover

(2)

Zirconia

(3)

Clogging



COMPONENT DESCRIPTION


(1)

Atmosphere

(A)

Electromotive force

(2)

Exhaust

(B)

Air fuel ratio

(3)

ZrO 2

(C)

Lean

(4)

Ceramic heater

(D)

Rich



ENABLE CONDITION

Secondary Parameters Enable Conditions
All secondary parameter enable conditions

More than 1 second

Battery voltage

> 10.9 V

Atmospheric pressure

> 75.1 kPa (563 mmHg, 22.2 inHg)

Closed loop control with main feedback

Operating

Impedance of front oxygen (A/F) sensor

0 ←→ 50 Ω

After engine starting

120 seconds or more

Engine coolant temperature

≥ 70°C (158°F)

Engine speed

1000 ←→ 3200 rpm

Vehicle speed

10 ←→ 120 km/h (6.21 ←→ 74.6 MPH)

Amount of intake air

10 ←→ 40 g (0.35 ←→ 1.41 oz)/s

Engine load change during 0.5 engine rev.

≤ 0.02 g (0.001 oz)/rev

Learning value of EVAP conc. during purge

≤ 0.2

Total time of operating canister purge

20 seconds or more



GENERAL DRIVING CYCLE

Perform diagnosis only once at a constant speed of 10 to 120 km/h (6.21 to 74.6 MPH) in 120 seconds after starting the engine.

DIAGNOSTIC METHOD

Integrate the difference of faf in every 128 milliseconds and difference of λ value.

After integrate 210 seconds, calculate the diagnosis value.

Judge NG when the malfunction criteria below are completed. Judge OK and clear NG when the malfunction criteria below are not completed.

Judgment Value

Malfunction Criteria Threshold Value
parafca = td2faf/td2lmd

≥ 0.269

where,

td2faf (N) = td2faf (n−1) + |d2faf (n)|

td2lmd (N) = td2lmd (n−1) + |d2lmd (n)|

add up for a total of 210 seconds

d2faf (n) = (faf (n) − faf (n−1)) − (faf (n−1) − faf (n−2))

d2lmd (n) = (lmd (n) − lmd (n−1)) − (lmd (n−1) − lmd (n−2))

faf = main feedback compensation coefficient every 128 milliseconds

lmd = output lambda every 128 milliseconds



Time Needed for Diagnosis: 210 seconds

Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cycles.

DTC CLEAR CONDITION


When the OK idling cycle was completed 40 times in a row

When “Clear Memory” was performed


MALFUNCTION INDICATOR LIGHT CLEAR CONDITION


When the OK driving cycle was completed 3 times in a row

When “Clear Memory” was performed


FAIL SAFE


Front oxygen (A/F) sensor main learning correction: Not allowed to calculate.

A/F sub learning correction: Not allowed to calculate.

Correction when re-starting at high temperature: Normally minimum value 0.3 → 0.

Purge control: Not allowed to purge.


ECM OPERATING AT DTC SETTING


Memorize the freeze frame data. (For test mode $02)

Memorize the diagnostic value and trouble standard value. (For test mode $06)