P0856moderate severityPowertrain
Traction Control Input Signal
on 2007 Ram 3500 5.9L I6 Cummins · 4WD
What this code means
The PCM detects a fault in the traction control input signal to the powertrain. This can disable traction control coordination with the engine and transmission.
Symptoms
- Traction control light on
- Reduced engine performance
- ABS/traction faults present
Common causes
- Faulty CAN communication with ABS module
- Wiring fault in signal circuit
- Failed traction control module
- Poor ground or connector corrosion
Diagnostic steps
- Retrieve codes from PCM and ABS module
- Check CAN bus communication integrity
- Inspect signal wiring and connectors
- Repair circuit or replace faulty module
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0006
Fuel Shutoff Valve A Control Circuit Low
P0007
Fuel Shutoff Valve A Control Circuit High
P0008
Engine Position System Performance - Bank 1
P0009
Engine Position System Performance - Bank 2
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1