Subaru 2009 IMPREZA Service Manual page 1817

Diagnostic Trouble Code (DTC) Detecting Criteria
EP:DTC P2444 SECONDARY AIR INJECTION SYSTEM PUMP STUCK ON
1. OUTLINE OF DIAGNOSIS
Detect the secondary air pump malfunction (always ON).
After the secondary air pump turns to OFF, judge as NG if the secondary air pipe pressure is higher than that
before the secondary air pump operation.
2. ENABLE CONDITIONS
Secondary Parameters
Battery voltage
Engine
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
• Abnormality Judgement
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Judgement Value
Malfunction Criteria
Time since secondary air control com-
pletion
Secondary air pipe pressure – Second-
ary air pressure before operation
Time Needed for Diagnosis: 8000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
• Normality Judgement
Judge as OK and clear the NG if the continuous time while the following conditions are established is more
than the predetermined time.
Judgement Value
Malfunction Criteria
Time since secondary air control com-
pletion
Secondary air pipe pressure – Second-
ary air pressure before operation
Time Needed for Diagnosis: 8000 ms
Enable Condition
7 V
In operation
Threshold Value
3000 ms
and
8000 ms
> 6.7 kPa
(50 mmHg, 2 inHg)
Threshold Value
3000 ms
and
8000 ms
6.7 kPa
(50 mmHg, 2 inHg)
GD(H4DOTC)-229
GENERAL DESCRIPTION