Cummins ISB CM850 (2003-06) Fault Code: 242 PID: 84 SPN: 84 FMI: 10 Vehicle Speed Sensor Circuit Tampering Has Been Detected – Abnormal Rate of Change. Invalid or inappropriate vehicle speed signal. Signal indicates an intermittent connection or VSS tampering.
Verify that the feature settings for the vehicle speed sensor anti-tampering (Fault Code 242), application type and automatic transmission are set correctly. If any of these are set incorrectly for your specific vehicle and application, Fault Code 242 could occur erroneously.
Driving techniques such as driving for extended periods of time in lower gears can log Fault Code 242. Fault Code 242 can be logged if the driver attempts to defeat the road speed governor by repeatedly cycling the keyswitch.
Once the speed signal has been restored the fault code will go inactive once the keyswitch is on for 30 seconds and the ECM senses zero vehicle and engine speed.
1)Remove the tampering device. Install the sensor correctly or remove the external device.
2)Repair or replace the OEM harness.
3)Replace the ECM.
Cummins ISB CM850 (2003-06) Fault Code: 241 PID: 84 SPN: 84 FMI: 2 Vehicle Speed Sensor Circuit – Data Erratic, Intermittent or Incorrect. The ECM lost the vehicle speed signal.
Cummins ISB CM850 (2003-06) Fault Code: 238 PID: SID 232 SPN: 611 FMI: 4 Sensor Supply 3 Circuit – Voltage Below Normal, or Shorted to Low Source. Low voltage detected on the +5 volt sensor supply circuit to the engine speed sensor.
Cummins ISB CM850 (2003-06) Fault Code: 237 PID: SID 30 SPN: 644 FMI: 2 External Speed Command Input (Multiple Unit Synchronization) – Data Erratic, Intermittent, or Incorrect. The throttle input signal to the primary or secondary engine for multiple unit synchronization is less than 3 percent or more than 97 percent.
Cummins ISB CM850 (2003-06) Fault Code: 235 PID: 111 SPN: 111 FMI: 1 Coolant Level – Data Valid but Below Normal Operational Range – Most Severe Level. Low engine coolant level detected.
Cummins ISB CM850 (2003-06) Fault Code: 234 (Marine) PID: 190 SPN: 190 FMI: 0 Engine Crankshaft Speed/Position – Data Valid but Above Normal Operational Range – Most Severe Level. Engine speed signal indicates engine speed above engine protection limit.
Cummins ISB CM850 (2003-06) Fault Code: 234 (Auto) PID: 190 SPN: 190 FMI: 0 Engine Crankshaft Speed/Position – Data Valid But Above Normal Operating Range – Most Severe Level. Engine speed signal indicates engine speed above engine protection limit.
