ABS/ESP Error C1391

[ragingraven]

Good evening.
I have a 2017 C4 Grand Picasso 120HP Diesel. When I press the accelerator pedal to ~3800 rpm, I get an error for ABS/ESP.
This happens both when driving and standing on place. I checked it with Diagbox and the error is C1391 "Engine torque not cleared fault". What could this be about?

Thanks in advance.

[GiveMeABreak]

You may need a software update if you are having both P0234 and C1391. If it's just the C1391, then it's non-acknowledgement of the engine torque fault: Not characterised. The signal specifying the status of the ESP functions in the deceleration phase and of the traction control, coming from the engine ECU, is at a value that is invalid or non-defined for at least 500 ms.

[ragingraven]

Just having the C1391 error, there was one other error about microphone 1, but nothing for engine or anything else.
Is there a screen/menu in Diagbox, where I can see the value coming from the ECU? Also if it's invalid/non-defined, then why is it happening? Bad wiring/fuses/sensors?

[GiveMeABreak]

Let me have your VIN and I might be able to get the full code descriptor as it applies to your vehicle (please post your VIN in full without spaces - it will be automatically masked from public view after submitting your post & will only be visible to staff). If I can't get back to you tonight, it will be tomorrow.

[ragingraven]

VIN is: VF7**************[VIN obfuscated, can be read by forum staff]
Have been getting this error for about 2 months now, tested with Diagbox software just this Saturday.

[ragingraven]

Any luck finding anything?
I read some other forums and people suggest checking battery voltage, mine was 12,7 V, which is good aparrently.

[GiveMeABreak]

Hi, thanks for reminding me - I hadn't bookmarked this topic, so it slipped through - I'll take a look now for you...

[GiveMeABreak]

Ok, so here is the fault as it relates to the system on your vehicle:

Fault Code:	C1391 00
Description of Fault:	Non-acknowledgement of the engine torque fault: Not characterised. The signal specifying the status of the trajectory control in deceleration phase and the traction control functions, coming from the engine ECU, is at a value that is invalid or not defined. The time for recording the fault code is 500 milliseconds.
Conditions for Fault to clear:	Ignition on (For at least 30 seconds)
Downgrade Modes whilst Fault is active:	Inhibition of one or more driving aid functions (*) Inhibiting of the electric parking brake function One or more messages from one of the driving aid functions (*) "SERVICE" warning lamp Orange "(P)!" warning lamp Message "Electric parking brake fault"
Symptoms:	Malfunction of the adaptive cruise control (ACC) Malfunction of the cruise control and/or speed limiter Poor behaviour of the vehicle on braking Malfunction of the electronic stability program (ESP) function Malfunction of the hill start assist (ADEC) Emergency collision braking not suited to the vehicle situation Malfunction of the semi-automatic parking assistance function (*) Malfunction of the automatic parking assistance function (*) Malfunction of the descent control system Malfunction of the electric parking brake
Suspect Areas:	Engine management ECU Connectors Harness ABS/ESP ECU

Note the '*' will mean warnings will depend on options fitted to your vehicle

[Flipmepoo]

French cars don't you just love them
They get plagued with electrical faults that normally always end up getting fixed , then You sell the car and buy another one, go through all the same thing and regret selling the last one

We've had this fault for months , with abs , esp , and handbrake fault on dash. Scan tool picked up lh wheel coherence and the fault in this topic, all relating to abs .Just managed to fix it. This may sound odd, but check your CV boots.
The Mrs 3008 had a split CV on pass side (lh) I knew and don't get round to doing it (mistake)This was spraying CV grease out whilst driven all over the abs sensor. At first I thought it was the sensor, changed it, no joy. Then if you look up where the abs rings are on these, they are integrated into the wheel bearing on the back of the hub, no rings as such. These rust bad and can fail. So I took the hub off and changed the driveshaft and CVS, as £25 for a second hand one off eBay easier and less messy than changing the boots . Cleaned everything as was a lot of grease that had been sprayed , completely covering abs sensor and bearing faces. Didn't make any difference, so I thought I will have to buy a new hub. I've just got back from a drive to Spain , thinking I will fit the new hub, however after another 100 work miles by the misses the fault is now only coming on intermittently. Been out and cleared the codes , driven up the road voila back to normal. Cruise working again.
Check for grease contamination on wheel bearing and abs sensor , and split CV boots before anything else

[ragingraven]

Decided to return to this topic instead of posting new one.

Haven't had any luck with eliminating the error, have MOT test in two weeks and last year I got a warning for the error.
Things I have done to try and eliminate the problem:
• Checked all wires connected to ABS and Engine ECU, no loose wires or anything.
• Checked all four wheels, brakes and wires connected to them, nothing wrong here.
• Changed brake discs, calipers, and pads, all new now.
• Checked CV boots from Flipmepoo's comment, like new, no grease contamination, no nothing.
• Checked wheel bearings from Flipmepoo's comment, nothing wrong here.

Thinking it might be something to do with ECU update. At least that's what official dealer service said me. But they refuse to elaborate without me paying 75€/h...
Attaching a PDF file with the error C1391 and a video of the error popping out on the dash (This will result a warning in MOT test...).
After error pops, map opens on the dash and tries to direct me to official dealer shops.





Once again, no other errors in Diagbox. Error happens when triggering the 2nd accelerator switch, ~3600rpm, no matter stopped or driving.

Thankful for any and all help you can provide!

[R0ssco82]

Did you manage to fix your problem ?

I have a peugeot 3008 with similar issue .
When rpm reaches 3000 i get the abs light with fault codes
c1391 non comfirmation of engine torque
P0337 engine speed signal incoherent

Car drives fine with or without faults , a cycle of the key and lights are out until revved to 3000 rpm ,

Tried crank sensor and plug with no change ...

[RichardW]

What engine is in it?

[ragingraven]

What engine is in it?

Engine is DV6FC
2017 Citroen Grand Picasso II 1.6 BlueHdi 120hp

[ragingraven]

Did you manage to fix your problem ?

I have a peugeot 3008 with similar issue .
When rpm reaches 3000 i get the abs light with fault codes
c1391 non comfirmation of engine torque
P0337 engine speed signal incoherent

Car drives fine with or without faults , a cycle of the key and lights are out until revved to 3000 rpm ,

Tried crank sensor and plug with no change ...

No, haven't managed to fix this problem, the fault goes away after restarting car, the same as for you.
No P0337 though, just the C1391

[R0ssco82]

Ok thanks ragingraving .. If i get to the bottom of mines will post the solution in case it helps you in any way .