Citroen C4 Picasso ABS/ESP Pump/ECU Replacement

[lmsvvavr]

Hi everyone!

As per the title...
I have this 2008 C4 Picasso 1.6HDI which is giving errors on pretty much every ECU...
However when scanned, all ECUs report problems related to the ABS/ESP ECU, for example, there is no speedo, and dash shows no info/communication from the ABS/ESP unit.
When I try to scan the ABS/ESP ECU I get an error saying something like no communication...
Even using Lexia...
However if I disconnect the unit the car will not start. (think because the can line is interrupted?)

Anyway, the part number of the unit is 96 651 066 80
The closest number I could find is 96 651 965 80

The question is, would this pump work?

[fruti]

Mate check feeding. I have same situation once and problem vas ignition + from bsi. Check fuses and relays. I think you dont get feeding on ecu .....
Cheers

[lmsvvavr]

Mate check feeding. I have same situation once and problem vas ignition + from bsi. Check fuses and relays. I think you dont get feeding on ecu .....
Cheers

Hi

Thank you for the reply...
I have checked that, although I don't have the pinout or wiring diagrams... there is two bigger contacts at each end of the plug... at one end there is ground on both contacts, at the other end one of them is 12v straight from the battery, the other one is going to the fuse F7 on top of the battery... fuse is ok and there is also 12v on it...
The rest of the contacts they should be wheel sensors, can and the rest I don't know...
Where can I get hold of the diagram for this?
Thank you

[lmsvvavr]

There is anyone that can share the abs circuit diagram for this?

[lmsvvavr]

Hi

There is no one that can share the wiring diagrams for this pump?
I have tried another pump, and made no difference...

[lmsvvavr]

I've download sedre but still trying to get it to work. ..
In the mean time, someone could please share that wiring diagram of the abs pump?
I'm desperate, the weather is changing to rain... and I am working on the drive way...

[lmsvvavr]

I have now managed to get SEDRE working...
Thank you all...

[lmsvvavr]

I have now managed to get SEDRE working...
Thank you all...

[lmsvvavr]

So, still no joy...

Some feedback about where I am with this problem...
After managed to get SEDRE to work, I started to measure the wires.

All less than 1 Ohm.

So, I have also checked the diagram for the diagnostic socket, and noticed that all communication wires go straight to the BSI.

Now my theory, because I cannot even diagnose the ABS/ESP ecu, and all the others report communication problems with it, I am presuming something is wrong with the BSI...

Does this make any sense to anyone?

[angelvoodoo]

hello friend.
i had a similar problem on a 307.
although when i measured wires continuty and voltage it was ok abs module did not work.
problem was, inside the plug of the harness at the point that cable connected to pin, water was inserted and damage the connection.and voltage was not good enough
my advise is to carefully remove all power cables and check the connections pin to cable.

[lmsvvavr]

hello friend.
i had a similar problem on a 307.
although when i measured wires continuty and voltage it was ok abs module did not work.
problem was, inside the plug of the harness at the point that cable connected to pin, water was inserted and damage the connection.and voltage was not good enough
my advise is to carefully remove all power cables and check the connections pin to cable.

Hi

Thank you... visually they look new... no corrosion or oxidisation, neither on the plug or pump.
I will have another look, just in case I have missed something.

[lmsvvavr]

Hi

Thank you... visually they look new... no corrosion or oxidisation, neither on the plug or pump.
I will have another look, just in case I have missed something.

Hi

Another day spent on the car...
I checked the CAN lines... Just in case... they are all good.
Accordingly SEDRE the CAN goes from the BSI to the EPB, then ESP/ABS and end up at the engine ECU.
That's the reason why the car does not start with the ABS/ESP disconnected.. as the CAN lines are interrupted before the engine ECU.

Like I said I have measured the can from the EPB up to the ABS/ESP and got less than 1 ohm.

Now, Lexia says that there is no communication with the ABS/ESP unit, as the CAN lines are ok, and the + and - 12volts are good, the only thing left is the remote control wake-up information, which is the wire 7842U, pin 35 at the ABS/ESP plug, and wire 7842P, pin 10 plug 40V NR on the BSI.

All the other wires are sensors and switches... which should not interferer with the communication with the unit.

Now, the wire is good, also less than 1 ohm, so I believe now that the BSI is not sending the signal to wake-up the ABS/ESP...

A new or second hand BSI hopefully it will solve the problem...

Does any one knows what the wake-up signal is? Is that 12volts, 5 volts or is just DATA.... thinking if I could force it to wake-up....

Any thoughts out there?

[lmsvvavr]

Hi
Finally found the problem...
Just need next days off to get it sorted...
Soon will update...

[kanzus]

Hello,
I face exactly same problem as you.
Changed ESP/ABS ECU, changed used BSI (copy/paste flash and eep from original with smok) and same problem.

Checked wires and seem ok.

Please could you help me ?

[lmsvvavr]

Hi

I do apologise for not feedback...
I have indeed resolved the problem, and was lack of 12v on one of the wires to the abs pump.
I am busy at work, as soon as I can I will post pictures of the problem...
Stay in standby...

[lmsvvavr]

As promised...

257447 257448 257450 257451 257452

The photos are self explanatory of the problem...
I have replaced the damaged wires sections, insulate them with glued shrink tubing.
Hope that helps...

[kanzus]

Thank you for pics and fast reply.
Will open loom and check wires.

[kanzus]

Hello,
I checked all wiring of loom from ABS to bsi and bsm, but nothing special, all ok.
Question: is relay part number 9652021180 is for ABS ?

258325
Regards

[kanzus]

Solved,
Blue wire coming from Battery Big Fuse plate was broken.
Thanks for all for your help.

Think that PSA looms are not well made !

[CSL JAY]

Solved,
Blue wire coming from Battery Big Fuse plate was broken.
Thanks for all for your help.

Think that PSA looms are not well made !

Having the exact same issue, blue wire looks fine around the battery area but do you know exactly where it goes? directly to power up ABS ECU?

[bondcars]

i would like to view photos

[cl90]

i have the same problem with a c4 picasso. no wake up till the ignition is turned on

[superdupersonic]

same problem here, no communication with abs/esp, checked all wires, replaced ecu, bsi and bsm.. any idea?

[pexip]

I have c1350 electrovalve problem
lexia says that voltage is about 9.5 V, is this correct level.

[Clint221]

Having the same problem.

[HollyAmelia01]

Having the same problem.

I have the Parling Brake, ABS and ESP warning messages on the dash after driving for 30 secs. Service ABS and ESP lamps on.

[lmsvvavr]

I have the Parling Brake, ABS and ESP warning messages on the dash after driving for 30 secs. Service ABS and ESP lamps on.

Think you have some work ahead... have you scanned the car?

[Carlos Fandango]

Hi All, can I just thank Imsvvavr for starting this thread and therefore helping me out. I had similar problems with my 2007 C4 picasso 1.6 HDI. ESP fault, ABS light on, Service light on, No speedometer, Pre-tensioner/airbag light on etc. one of many fault codes read 'Lost ABS comms'.

I followed the methods that were employed to detect the fault including the pictures Imsvvavr posted and stripped out the battery, BSI unit, ECU etc so as to gain access to the wiring loom as in the pictures. As I unwrapped the wiring loom back I found that the small thin blue wire from the top of the battery fuse box plate (5 amps) {ESP ecu feed} had already had a repair to it in the form of a soldered piece of black wire inserted where the blue wire had broken at some time prior. As this is a known fault I was a little disappointed that this was not my fault. I kept checking the wire for continuity all the way down and eventually ended up taking the N/S/F wheel off and the inner wing splash guard down to gain access to the ABS unit.

After struggling in the confined space I got a little bit annoyed and said to a colleague "all I want to do is probe this ******* thin blue wire"and lifted it with my test meter probe. At this point the wire moved and after pulling on it gently it emerged from the bottom curvature of the loom broken. Strip the loom back, find the other broken end and repair the break with a soldered piece of replacement blue wire! Re-built the whole lot, tested the system......... all lights now extinguished. Be careful not to confuse the thin blue wire with another blue wire that is paired with a pink wire as a 'twisted pair' for the can bus. These went to the ABS plug pretty close together.

Thanks again to Imsvvavr for starting the thread and I hope that this post may help some other unfortunate individual who may need their C4 'pains' cleansing!

PS The wire that I repaired was the same wire that had been previously repaired further up the loom.

PPS One wire break can cause all that carnage! Think I'll go buy a Moggie thousand.

[lmsvvavr]

Hi All, can I just thank Imsvvavr for starting this thread and therefore helping me out. I had similar problems with my 2007 C4 picasso 1.6 HDI. ESP fault, ABS light on, Service light on, No speedometer, Pre-tensioner/airbag light on etc. one of many fault codes read 'Lost ABS comms'.

I followed the methods that were employed to detect the fault including the pictures Imsvvavr posted and stripped out the battery, BSI unit, ECU etc so as to gain access to the wiring loom as in the pictures. As I unwrapped the wiring loom back I found that the small thin blue wire from the top of the battery fuse box plate (5 amps) {ESP ecu feed} had already had a repair to it in the form of a soldered piece of black wire inserted where the blue wire had broken at some time prior. As this is a known fault I was a little disappointed that this was not my fault. I kept checking the wire for continuity all the way down and eventually ended up taking the N/S/F wheel off and the inner wing splash guard down to gain access to the ABS unit.

After struggling in the confined space I got a little bit annoyed and said to a colleague "all I want to do is probe this ******* thin blue wire"and lifted it with my test meter probe. At this point the wire moved and after pulling on it gently it emerged from the bottom curvature of the loom broken. Strip the loom back, find the other broken end and repair the break with a soldered piece of replacement blue wire! Re-built the whole lot, tested the system......... all lights now extinguished. Be careful not to confuse the thin blue wire with another blue wire that is paired with a pink wire as a 'twisted pair' for the can bus. These went to the ABS plug pretty close together.

Thanks again to Imsvvavr for starting the thread and I hope that this post may help some other unfortunate individual who may need their C4 'pains' cleansing!

PS The wire that I repaired was the same wire that had been previously repaired further up the loom.

PPS One wire break can cause all that carnage! Think I'll go buy a Moggie thousand.

Hi
Glad to know that the post still helping people out there, thank you for the feedback!
Hope you have visited my YouTube channel... unfortunately I was not recording at the time of this repair... lol

[Carlos Fandango]

Hi Imsvvavr, Nice to see you are recording faults/repairs now although the pictures you took were more than good enough to help me out. I would have taken some pictures of my repair but was thwarted due to time constraints in the location that I was carrying out the diagnosis/repair. Hopefully I have described it well enough in order to help others out.

Many thanks again, Carlos.

[lmsvvavr]

Hi

For you that are having this issue, and you have seen the photos above, I would like to share with you another exact same problem...
I had this C4 last week, and I remembered the problem I had when I have originally opened this thread...
Hope you find it useful...

https://youtu.be/Jh9Ctv-1WlU

[eamon1992]

Hi I have 09 citroen c4 picasso 1.6 hdi automatic . similar symptoms like you had but I have braking system faulty and car wont crank. also I cant connect to abs ecu or esp ecu. only code i got U1313. Any help appreciated. Thanks

[lmsvvavr]

Hi I have 09 citroen c4 picasso 1.6 hdi automatic . similar symptoms like you had but I have braking system faulty and car wont crank. also I cant connect to abs ecu or esp ecu. only code i got U1313. Any help appreciated. Thanks

Hi
That means your ABS module is completely offline... It needs to be working in order for the engine to start, as the CAN runs then from the ABS to the engine ECU... so if the ABS module is off, then no comms get to the engine ECU.
Check your grounds and voltages to the ABS module... most likely that will be you issue!

[eamon1992]

Hi thanks for your reply . I will check tomorrow. Is there any relay for abs ?

[eamon1992]

Hi checked them all and its all good. Any way that the fuse box on the top of battery had fail ?

[eamon1992]

Hi thanks for your help got it sorted today (I think) car started and all faults went away. I cleaned the fuse box on the top of battery . I see in the morning if car starts, Thanks again

[DanDD]

Same problem here. ABS/ESP fault, parking break fault, engine management fault, gearbox fault, air bags system fault, service and stop illuminated etc etc. Everything began suddenly after the car was on the rain/cold 2 weeks ago for not been driven for 2-3weeks. Started the engine and all faults appeared out of the blue. The battery was very weak as well.
Already had a look for the famous blue wire feed for the ABS module but not sure which one exactly is.
Das anyone have the diagrams?

[nigelelyons]

Another successful fix - corroded blue wire in wiring loom! I was very reticent to strip loom too much as it looked in great condition for the first few inches at each end. But right in the middle along the bulkhead behind battery the thin blue wire was corroded and severed internally. A quick insertion of a link between the break and all the errors have gone. Unbelievable! To help others I had had the following faults. ABS Fault, Brake fault, EPS fault, Depollution fault, Handbrake fault, Gearbox fault, Power steering fault. EGS Gearbox would only change using paddles from 1st up to 3rd. To get further I had to accelerate and drop into Neutral and then back into Auto mode to get 5th or 6th. Gearbox changed down fine! Speedo was just 2 dashes. ODB II reader showed lots of CAN bus errors. Blue wire sorted everything apart from Depollution error. Hopefully a reset and few miles will clear it too. MANY MANY THANKS !!!!!

[brendancollis]

I've given in on mine so it's booked in to a Citroen specialist. I have checked all the relays fused, stripped the loom and all good, checked break switch then brought all new ABS sensors and plugged in and still no joy. Unless someone has any other reasons I guess I'm in for a hefty bill.