P0102

DTC P0102 - MASS OR VOLUME AIR FLOW CIRCUIT LOW INPUT

OUTLINE OF DIAGNOSIS
Detect the open or short circuit of air flow sensor. Judge NG when out of the standard value.




COMPONENT DESCRIPTION




ENABLE CONDITION

GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.

DIAGNOSTIC METHOD




Judge NG when the continuous time of completing the malfunction criteria becomes more than 0.5 seconds. Judge OK and clear the NG when the malfunction criteria are not completed.

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
- Airflow meter: Engine load is normally calculated by manifold pressure and engine speed; however, calculated only by manifold pressure. EVAP cone. learning (fuel): Not allowed to learn.
- Knock compensation:
- Knock compensation final timing advance and retard value = knock compensation + whole learning compensation value + partial learning compensation value.
- At normal: knock compensation = 0 °CA is fixed.
- At trouble: knock compensation NOT EQUAL TO 0 °CA is fixed. (Retard max. 12 °CA at knock.)
- Not allowed to update the whole learning compensation factor.
- Not allowed to calculate the partial learning zone compensation value.

- ISC control: Make the open loop compensation to be the given value (1 g/s). Stop calculating the throttle sensor temperature compensation. (Hold the previous value.)
- Purge control: Not allowed to purge.

ECM OPERATING AT DTC SETTING
Memorize the freeze frame data. (For test mode $02)