Le P0235 signifie un pb de capteur de pression de turbo. Plusieurs problèmes sont recensé sous le même code.
Voila ce qu'en dit la doc sur les causes possibles:
1- Symptom:
P0235-BOOST PRESSURE SENSOR PLAUSIBILITY
When Monitored and Set Condition:
When Monitored: With the engine speed below 850 rpm.
Set Condition: When the engine is idling, the boost pressure sensor input does not agree
with the barometric pressure sensor input for at least 5 seconds.
POSSIBLE CAUSES
INTERMITTENT CONDITION
HIGH RESISTANCE IN THE BOOST PRESSURE SENSOR SIGNAL CIRCUIT
HIGH RESISTANCE IN THE BOOST PRESSURE SENSOR GROUND CIRCUIT
HIGH RESISTANCE IN THE 5-VOLT SUPPLY CIRCUIT
BOOST PRESSURE/INTAKE AIR TEMPERATURE SENSOR
ENGINE CONTROL MODULE
TEST ACTION APPLICABILITY
2- Symptom:
P0235-BOOST PRESSURE SENSOR SIGNAL VOLTAGE TOO HIGH
When Monitored and Set Condition:
When Monitored: With the ignition on.
Set Condition: The Boost Pressure Sensor Signal voltage exceeds 4.5 volts for at least 2
seconds.
POSSIBLE CAUSES
INTERMITTENT CONDITION
5-VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE
BOOST PRESSURE SENSOR GROUND CIRCUIT OPEN
BOOST PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE
BOOST PRESSURE/INTAKE AIR TEMPERATURE SENSOR
POOR CONNECTOR TERMINAL CONTACT
ENGINE CONTROL MODULE (5-VOLT SUPPLY SHORTED TO VOLTAGE)
ENGINE CONTROL MODULE (INTERNAL)
ENGINE CONTROL MODULE (SENSOR SIGNAL SHORTED TO VOLTAGE)
3- Symptom:
P0235-BOOST PRESSURE SENSOR SIGNAL VOLTAGE TOO LOW
When Monitored and Set Condition:
P0235-BOOST PRESSURE SENSOR SIGNAL VOLTAGE TOO LOW
When Monitored: With the ignition on.
Set Condition: The Turbocharger Boost Pressure Sensor Signal voltage is below 0.15 volt
for at least 2 seconds.
POSSIBLE CAUSES
INTERMITTENT CONDITION
5-VOLT SUPPLY CIRCUIT OPEN OR SHORTED TO GROUND
BOOST PRESSURE/INTAKE AIR TEMPERATURE SENSOR
BOOST PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO GROUND
BOOST PRESSURE SENSOR SIGNAL AND GROUND CIRCUITS SHORTED TOGETHER
BOOST PRESSURE SENSOR SIGNAL CIRCUIT OPEN
ENGINE CONTROL MODULE
4- Symptom:
P0235-BOOST PRESSURE SENSOR SUPPLY VOLTAGE TOO HIGH
OR LOW
When Monitored and Set Condition:
When Monitored: With the ignition on.
Set Condition: The Sensor Reference Voltage 9B9 voltage to the Boost Pressure Sensor is
below 4.8 volts or above 5.2 volts for at least 100 ms.
POSSIBLE CAUSES
INTERMITTENT CONDITION
5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
5-VOLT SUPPLY CIRCUIT SHORTED TO SENSOR GROUND
5-VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE
APP SENSOR 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
APP SENSOR 5-VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE
ENGINE CONTROL MODULE
Les procédures de tests sont décrites dans le doc 02kjed.pdf que tu trouveras ici
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