Error Codes Article - P0234 Turbo Boost Limit Exceeded

[Mopar1973Man]

DTC P0234: TURBO BOOST LIMIT EXCEEDED

Monitor & Set Conditions

Turbo boost limit is monitored when the ignition is on. DTC may be stored if Engine Control Module (ECM) senses engine speed is greater than 2200 RPM with no intake air pressure sensor out of range DTCs present.

Possible Causes

• Mechanical Wastegate Failure
• Wastegate Stuck

Testing

1. Turn ignition on with engine off. Using DRBIII(R) scan tool, check for DTCs. If DTC Good Trip Counter is not equal to zero for P0234, go to next step. If DTC Good Trip Counter is equal to zero for P0234, replace wastegate. It may be necessary to replace turbocharger and wastegate as an assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.

2. Ensure ignition is on with engine off. Using scan tool, read and record FREEZE FRAME data. Road test vehicle under conditions displayed in FREEZE FRAME data and note DTC Good Trip Counter for P0234. If DTC Good Trip Counter does not change to zero, the test is complete. If DTC Good Trip Counter changes to zero, replace wastegate. It may be necessary to replace turbocharger and wastegate as an assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.

 

 

 

Mopar1973man.com Tip

 

Probe the map sensor output wire, pin c of the sensor, using a multimeter at Idle state.  The Sensor should be outputting near 4.5v.  anything more than .25 less than that means your map sensor is reading boost at idle.  If it reads .5v at idle then you will trip a code p0237, but if it reads ~4v-1v at idle then you will get this p0234 code.  

 

effectively means the map sensor is stuck reading a single psi reading and not functioning.

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