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.
P0237 is set when BPS output voltage is lower than minimum value (200mV) for more than 2 sec.. This code is due to 1) open in power circuit or 2) short to ground in signal circuit.
Item
Detecting Condition
Possible Cause
DTC Strategy
Voltage monitoring
BPS circuit
BPS
Enable Conditions
IG key ON
Threshold Value
Output voltage is lower than minimum value (200mV).
- Open in power circuit.
- Short to ground in signal circuit.
Diagnostic Time
2 sec.
Fail Safe
Fuel cut
NO
-
EGR Off
YES
Fuel Limit
Check Lamp
ON
Pressure[Kpa]
32.5
70
140
210
270
284
Output voltage[V]
0.5
1.02~1.17
2.13~2.28
3.25~3.40
4.20~4.35
4.5
Fig.1) The waveform of BPS signal as accelerating from idle state. Signal voltage rises as accelerating.