Fault code F08

[TopStaf4d]

I’m looking for troubleshooting a F08 code on a 2017/18.

 

[Eagle1]

The should be an s-xxx code with the F08 but I believe F08 is an EGR position error.
s27 F08 (P0404) - EGR position control fault
Control Module: ECU
Context:
The Engine Control Unit (ECU) A-009 controls the operation of the Exhaust Gas Recirculation (EGR) valve Z-003
circuit. This fault will occur when the ECU senses a problem with the operation or the circuit of the EGR valve Z-005
motor, or if the EGR valve wiring harness is disconnected. Because of this fault, Diesel Particulate Filter (DPF) re-
generation will stop, EGR valve control will stop, ACV control will stop, an a reduction in engine torque may occur.
Cause:
The ECU senses a short to battery, short to ground, or open circuit condition in the EGR valve circuit wiring.
Possible failure modes:
1. Faulty EGR valve Z-005, internal failure.
2. Faulty EGR valve Z-005 driver circuit wiring, short or open circuit.
3. Faulty ECU A-009, software or hardware.

 

[GS650GL]

The other half of the code with the S is directly above the F08 and has an open book symbol to the left of it. The only code with an F08 on my fault code list is S27 F08 EGR position fault as stated in the previous reply by Eagle1. The EGR valve position sensor has failed or the valve is stuck. Either way, the EGR valve will need to be replaced. I think the part # is 40265792. It also prevents doing a regen so it will need a manual regen after the repair. This style EGR valve has been discontinued so they are getting scarce, but there are still a few left that dealers have in stock.

 

[alliscrawler57]

Check the EGR. Mine came apart and allowed hot exhaust gas into turbo feed ruining turbo. This was on a 4155.