U1308 also U1208

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Post Reply
pauljordanie
Posts: 62
Joined: 14 Nov 2018, 13:39
Location: Ireland
My Cars: 2009 Citroen C4GP

U1308 also U1208

Post by pauljordanie »

I get fault U1308 & U1208 regularly. This manifests itself by setting off ABS/ESP fault. When I plug in Lexia I get incoherence error between ECU and ABS ECU. Lexia indicates VIN as VF7**************[VIN obfuscated, can be read by forum staff] but Chassis VIN is VF7**************[VIN obfuscated, can be read by forum staff]. This leads me to think the ECU has been swapped out. I wonder is the fault associated with replacement of ECU? The error tends to happen more frequently at low road speed approx 45kph.....This problem is driving me cracked and I'm getting to the end of my tether with it. Anyone any ideas how I can diagnose this fault?
User avatar
GiveMeABreak
Forum Admin Team
Posts: 37005
Joined: 15 Sep 2015, 19:38
Location: West Wales
My Cars: C3 Aircross SUV HDi Flair Peperoncino Red (The Chili Hornet)
C5 X7 2.0 HDi Exclusive Mativoire Beige (The Golden Hornet)
C3 1.6 HDi Exclusive Aluminium Grey (The Silver Hornet)
C5 MK II 2.0 HDi Exclusive Obsidian Black
C5 MK I 2.0 HDi SX Wicked Red
Xantia S2 2.0 HDi SX Hermes Red
C15 Romahome White
XM 2.0 Turbo Prestige Emerald Green Pearlescent
XM 2.0 Turbo Prestige Polar White
XM 2.0 SX Polar White
CX 20 Polar White
GS 1220 Geranium Red
CX 2.4 Prestige C-Matic Nevada Beige
GS 1000 Cedreat Yellow
x 5646

Re: U1308 also U1208

Post by GiveMeABreak »

The BSI has obviously been swapped. Both those VINs relate to the same vehicle model and engine, so that's a start.

As for the faults, these both relate to the ABS / ESP ECU which A) is not getting any signal from the Engine Management ECU and B) is causing the second fault as a result of fault U1308.

U1308: No communication with the engine management ECU fault : No signal
U1208: No communication with the engine management ECU fault: Data invalid

So basically U1308 is saying the ABS/ESP ECU is not getting any signal from the engine ECU, which results in the second fault U1208, which basically is saying it can't understand the data - which makes sense as it can't if it's not getting anything in the first place.

So the focus needs to be on wiring connections from the ABS / ECU to the Engine ECU - check all connectors. Has any work been done on the brakes lately or any work generally? This won't be the first time we've found people have had work done and dislodged a connector or not put it back properly causing problems down the line.

Of course until this is fixed all your ESP functions will be disabled including hill start and some functions of the electronic parking brake, so be aware.
Please Don't PM Me For Technical Help

Marc
pauljordanie
Posts: 62
Joined: 14 Nov 2018, 13:39
Location: Ireland
My Cars: 2009 Citroen C4GP

Re: U1308 also U1208

Post by pauljordanie »

Thank you for the detailed response. I assume you mean problem on CAN bus between ECU and ABS ECU? If so only 2 wires to check? This problem is intermittent. The warning light is off at the moment but comes and goes, like I say its strange when the fault does appear I'm doing approx 46kph (taken from lexia)
User avatar
GiveMeABreak
Forum Admin Team
Posts: 37005
Joined: 15 Sep 2015, 19:38
Location: West Wales
My Cars: C3 Aircross SUV HDi Flair Peperoncino Red (The Chili Hornet)
C5 X7 2.0 HDi Exclusive Mativoire Beige (The Golden Hornet)
C3 1.6 HDi Exclusive Aluminium Grey (The Silver Hornet)
C5 MK II 2.0 HDi Exclusive Obsidian Black
C5 MK I 2.0 HDi SX Wicked Red
Xantia S2 2.0 HDi SX Hermes Red
C15 Romahome White
XM 2.0 Turbo Prestige Emerald Green Pearlescent
XM 2.0 Turbo Prestige Polar White
XM 2.0 SX Polar White
CX 20 Polar White
GS 1220 Geranium Red
CX 2.4 Prestige C-Matic Nevada Beige
GS 1000 Cedreat Yellow
x 5646

Re: U1308 also U1208

Post by GiveMeABreak »

Here's the ABS ESP ECU wiring:

Yes, the 9010 (High intersystem 2 CAN bus) and 9011 (Low intersystem 2 CAN bus)

Image

Again, given that you have said it is intermittent, I would really give those connectors a check - but also it is well-known that the state of the C4 Picasso wiring is atrocious - there have been cases where the wiring in the loom has just become brittle and broken causing all sorts of problems.

It can also be an issue of an incorrect / corrupt download to the engine ECU, but I would suspect you would have more errors if that was the case than just these two.
Please Don't PM Me For Technical Help

Marc
RichardW
Forum Treasurer
Posts: 10814
Joined: 07 Aug 2002, 17:12
Location: United Kingdom
My Cars: MK2 '17 C4GP 1.6 BlueHDi 120
'13 3008 1.6 HDi GripControl
x 984

Re: U1308 also U1208

Post by RichardW »

Check in the engine ECU for any EGR related fault codes. In a genius bit of programming, EGR faults cause loss of comms with the ABS ECU, but don't put the engine management light on!!
Richard W
pauljordanie
Posts: 62
Joined: 14 Nov 2018, 13:39
Location: Ireland
My Cars: 2009 Citroen C4GP

Re: U1308 also U1208

Post by pauljordanie »

Is component 1611 on the diagram the clutch pedal sensor?
User avatar
Chris570
(Donor 2020)
Posts: 1461
Joined: 12 Dec 2009, 14:10
Location:
My Cars:
x 29

Re: U1308 also U1208

Post by Chris570 »

RichardW wrote: 15 Feb 2019, 21:02 Check in the engine ECU for any EGR related fault codes. In a genius bit of programming, EGR faults cause loss of comms with the ABS ECU, but don't put the engine management light on!!

What he said^^^

That's what caused it on my Picasso
2006 C5 HDi 170
1998 Xantia Activa S1
1971 D Special
2006 C3 1.6 HDi SX,
CitroJim wrote: I'm a pink fairy
A 1/3 of Team WFA 'Clarkson'
pauljordanie
Posts: 62
Joined: 14 Nov 2018, 13:39
Location: Ireland
My Cars: 2009 Citroen C4GP

Re: U1308 also U1208

Post by pauljordanie »

I don't have any EGR faults logged. I do however have a clutch position sensor fault. I changed the switch and it made no difference and so I'm looking to check wiring continuity to both ABS ECU and engine ECU for consistency. When I drive with cruise control on and press the clutch the car comes out of cruise control so one of the ECUs is getting the correct signal.... Like I said prior its strange that the fault tends to happen when driving at 45/46 kph. Sometimes you can drive the car 200 miles and the ABS light doesn't come on..
Attachments
U1208.JPG
User avatar
GiveMeABreak
Forum Admin Team
Posts: 37005
Joined: 15 Sep 2015, 19:38
Location: West Wales
My Cars: C3 Aircross SUV HDi Flair Peperoncino Red (The Chili Hornet)
C5 X7 2.0 HDi Exclusive Mativoire Beige (The Golden Hornet)
C3 1.6 HDi Exclusive Aluminium Grey (The Silver Hornet)
C5 MK II 2.0 HDi Exclusive Obsidian Black
C5 MK I 2.0 HDi SX Wicked Red
Xantia S2 2.0 HDi SX Hermes Red
C15 Romahome White
XM 2.0 Turbo Prestige Emerald Green Pearlescent
XM 2.0 Turbo Prestige Polar White
XM 2.0 SX Polar White
CX 20 Polar White
GS 1220 Geranium Red
CX 2.4 Prestige C-Matic Nevada Beige
GS 1000 Cedreat Yellow
x 5646

Re: U1308 also U1208

Post by GiveMeABreak »

pauljordanie wrote: 11 Mar 2019, 14:51 Is component 1611 on the diagram the clutch pedal sensor?
1611: clutch release pedal angle position sensor
Please Don't PM Me For Technical Help

Marc
pauljordanie
Posts: 62
Joined: 14 Nov 2018, 13:39
Location: Ireland
My Cars: 2009 Citroen C4GP

Re: U1308 also U1208

Post by pauljordanie »

I traced clutch position sensor back to ECU and the ABS ECU and all fine. I managed to connect Lexia to the car and I cleared all the faults. I could see in the ABS ECU the position of the clutch position would change when I pressed it down and same with Bosch ECU. Once I do that I cleared all ECU fault codes and I get ECU communications coherence fault straight away and the ABS/Braking system warnings come on. Here is a screen shot of the version and sw version on the ECU. Does anyone know if there is a problem with these versions?
Attachments
20190312_153025.jpg
User avatar
Chris570
(Donor 2020)
Posts: 1461
Joined: 12 Dec 2009, 14:10
Location:
My Cars:
x 29

Re: U1308 also U1208

Post by Chris570 »

I've also seen this on a picasso I did a bsi swap on. Was everytime the clutch pedal went down it did it. I had to use lexia to recalibrate the sensor iirc. The option isn't in diagbox
2006 C5 HDi 170
1998 Xantia Activa S1
1971 D Special
2006 C3 1.6 HDi SX,
CitroJim wrote: I'm a pink fairy
A 1/3 of Team WFA 'Clarkson'
pauljordanie
Posts: 62
Joined: 14 Nov 2018, 13:39
Location: Ireland
My Cars: 2009 Citroen C4GP

Re: U1308 also U1208

Post by pauljordanie »

Here is an overview of the problem.

1) Sometimes I get ABS fault on dash, it tends to always happen at a specific speed - 45kph.
2) I can scan and read using Diagbox Lexia each of the vehicles ECU's. If I use an ELM or other cheaper handheld ECU reader I get no comms error and wont read codes. I think I should be able to read ECU on this car with cheap reader?
3) When I scan using Diagbox, lexia I get red warning lights come on the dash ABS faults auto parking brake etc as its doing the read from the ABS ECU.
4) Clear all faults on all ECU's. If I rescan at this point without driving car, red ABS fault lights come on dash again.
5) Clear all faults on all ECU's. Start car all ok, All is fine then again sometimes when driving at 45kph ABS fault light on.

I think I have 2 faults here. One is some kind of ECU comms issues between ABS ECU and engine ECU. The other is something happens when I drive at 45kph.
User avatar
GiveMeABreak
Forum Admin Team
Posts: 37005
Joined: 15 Sep 2015, 19:38
Location: West Wales
My Cars: C3 Aircross SUV HDi Flair Peperoncino Red (The Chili Hornet)
C5 X7 2.0 HDi Exclusive Mativoire Beige (The Golden Hornet)
C3 1.6 HDi Exclusive Aluminium Grey (The Silver Hornet)
C5 MK II 2.0 HDi Exclusive Obsidian Black
C5 MK I 2.0 HDi SX Wicked Red
Xantia S2 2.0 HDi SX Hermes Red
C15 Romahome White
XM 2.0 Turbo Prestige Emerald Green Pearlescent
XM 2.0 Turbo Prestige Polar White
XM 2.0 SX Polar White
CX 20 Polar White
GS 1220 Geranium Red
CX 2.4 Prestige C-Matic Nevada Beige
GS 1000 Cedreat Yellow
x 5646

Re: U1308 also U1208

Post by GiveMeABreak »

pauljordanie wrote: 13 Mar 2019, 09:48 Here is an overview of the problem.
1) Sometimes I get ABS fault on dash, it tends to always happen at a specific speed - 45kph.
May be a faulty Speed Sensor on one of the Wheels - but should store a code.
2) I can scan and read using Diagbox Lexia each of the vehicles ECU's. If I use an ELM or other cheaper handheld ECU reader I get no comms error and wont read codes. I think I should be able to read ECU on this car with cheap reader?
Not necessarily - cheaper readers may not have the necessary protocols to read certain ECUs - that is why a Lexia 3 System is recommended as it is a near dealer-level clone
3) When I scan using Diagbox, lexia I get red warning lights come on the dash ABS faults auto parking brake etc as its doing the read from the ABS ECU.
That is perfectly normal and part of the global diagnostic as the various systems are interrogated.
4) Clear all faults on all ECU's. If I rescan at this point without driving car, red ABS fault lights come on dash again.
See above - normal for these to come on during diagnosis
5) Clear all faults on all ECU's. Start car all ok, All is fine then again sometimes when driving at 45kph ABS fault light on.
That means there is a fault! Clearing the faults does not make them go away - as soon as the problem arises gain, it will trigger the faults and log a code. You need to see which codes are remaining.
I think I have 2 faults here. One is some kind of ECU comms issues between ABS ECU and engine ECU. The other is something happens when I drive at 45kph.
That is correct - you have a problem that occurs at speed, that triggers the faults and puts the ESP / ABS system into backup mode. This will keep happening so long as the problem remains.
Please Don't PM Me For Technical Help

Marc
RichardW
Forum Treasurer
Posts: 10814
Joined: 07 Aug 2002, 17:12
Location: United Kingdom
My Cars: MK2 '17 C4GP 1.6 BlueHDi 120
'13 3008 1.6 HDi GripControl
x 984

Re: U1308 also U1208

Post by RichardW »

That sort of speed is about where the Cruise becomes active, so it could well be to do with that threshold. If the BSI has been changed, then maybe it is not programmed correctly for the cruise; or as Chris570 says, the sensor needs to be calibrated. Seems unlikely that you couldn't do this in Diagbox for a modern car, but, hey, this is PSA so anything's possible!!
Richard W
Post Reply