lookupobd
Diagnostic Trouble Code
P0237

Turbocharger/Supercharger Boost Sensor A Circuit Low

Technical Description P0237

Generic: Turbocharger/Supercharger Boost Sensor "A" Circuit Low GM: Turbocharger Boost Circuit Low Input Conditions Dodge Chrysler: MAP Sensor Signal Too Low

What Does This Mean P0237?

This is a generic powertrain diagnostic trouble code (DTC) applicable to all turbocharged vehicles. Vehicle makes may include but are not limited to VW, Dodge, Mercedes, Isuzu, Chrysler, Jeep, etc.

The powertrain control module (PCM) monitors boost pressure with a sensor called the manifold absolute pressure sensor (MAP). Understanding how a MAP sensor works is the first step in explaining the cause of P0237.

The PCM sends a 5 volt reference signal to the MAP sensor and the MAP sensor sends a variable voltage signal back to the PCM. When boost pressure is high the voltage signal is high. When boost pressure is low the voltage is low. The PCM uses the boost control solenoid to control the amount of boost pressure that is produce by the turbocharger while at the same time using the boost pressure sensor to verify that the boost pressure is correct.

This code sets when the PCM senses a low voltage signal indicating low boost pressure when a high pressure command has been sent to the boost control solenoid "A".

Symptoms P0237

1 Check engine light will be on
2 Low engine power
3 Reduced fuel economy

Possible Causes P0237

1 Faulty boost sensor "A"
2 Faulty turbocharger
3 Faulty PCM
4 Wiring problem

Solutions & Repair Steps P0237

Before diagnosing P0237 be sure there are no other trouble codes present in the PCM memory. If there are other DTC’s present, they should be checked first. Any codes related to waste gate control or 5 volt reference will induce the conditions necessary to set this code. In my experience the PCM is the least likely cause of this problem. More often than not it is chafed or burnt wiring near the turbocharger causing shorts or opens in the circuit.

A good starting point is always to check for technical service bulletins (TSB) for your particular vehicle. Your issue may be a known issue with a known fix put out by the manufacturer and can save you time and money during diagnosis.