Boost Pressure Sensor(BPS) is installed in intake manifold and senses the pressure of air inside of intake manifold which is compressed by turbo charager.
Measuring mass air flow accurately with the information of intake mainfold pressure, mass air flow and intake air temperature, ECM performs actuating correction of EGR and VGT.
When excessive intake manifold pressure is detected, engine power generation is limited to protect engine because too highly compressed pressure due to turbo charger may harm engine.
P0238 is set when the voltage above 4.9V - maximum output voltage of BPS - is detected for more than 2 sec.. This code is due to 1) short to battery or open in signal circuit or 3) open in ground circuit.
Item
Detecting Condition
Possible Cause
DTC Strategy
? Voltage monitoring
? BPS circuit
? BPS component
Enable Conditions
? IG KEY "ON"
Threshold Value
? Output signal above maximum value(above 4.9V)
Diagnostic Time
? 2 sec.
Fail Safe
Fuel Cut
NO
? Boost pressure is fixed at 1000 hpa.
EGR Off
YES
Fuel Limit
Check Lamp
Pressure [Kpa]
20
100
190
250
Outpur voltage [V]
0.4±0.077
1.878±0.063
3.541±0.063
4.650±0.077