Engine Crankshaft Speed/Position – Data Valid but Above Normal Operational Range – Most Severe Level
|Fault Code: 234
Engine Crankshaft Speed/Position – Data Valid but Above Normal Operational Range – Most Severe Level. Engine speed signal indicates engine speed above engine protection limit.
Fuel injection disabled until engine speed fails below the overspeed limit.
Camshaft Position Sensor and Engine Speed Sensor Circuit
The crankshaft engine speed sensor and the camshaft engine position sensor provide engine speed and position information to the Electronic Control Module (ECM) through the engine harness.
The crankshaft speed sensor is located on the intake side of the engine near the number 6 cylinder at the crankshaft centerline. For ISB and QSB5.9 the crankshaft engine speed sensor is located on the intake side of the engine behind the vibration damper near the tone wheel. The camshaft speed sensor is located below the fuel pump in the back of the gear housing.
Possible causes of this fault code include:
- External fuel sources drawn into the intake air passage
- Reverse powering (motoring) of the engine
- Tampering of the engine speed/position sensors.
Inspect the intake manifold for sources of flammable vapors. Check the turbocharger seals to verify that there are no oil leaks. Inspect the engine speed/position sensors for damage or tampering.