What does it mean?
P1407 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Exhaust Gas Recirculation (EGR) Motor Control Circuit Shorted .
Symptoms
- MIL on, sometimes with reduced power
- Rough idle, hesitation and stalling
- Black smoke and a strong exhaust smell on diesel engines
- Loss of power or limp mode
- Higher fuel consumption
- Blown fuse in the circuit on some systems
Likely causes
- Short to ground or between phases in the EGR motor control wiring
- Internally shorted motor winding inside the EGR valve
- Carbon jamming the valve so the motor draws excessive current
- Corroded or water filled EGR valve connector
- Harness chafed against the engine block or an exhaust heat shield
- Damaged driver stage inside the control module
- A poor repair splice in the control circuit from earlier work
How to fix it
- Disconnect the EGR valve and measure each motor winding resistance plus the insulation to ground
- With the valve unplugged, test the control circuit for a short to ground
- Inspect the connector and harness for water, corrosion and chafe damage
- Remove the valve and confirm it moves freely, cleaning carbon from the pintle and seat
- Command the valve open and closed with a scan tool while watching position feedback and current draw
- Repair the shorted wiring or replace the EGR valve as required
- Verify the module driver output before fitting a new valve so the replacement part is not damaged