Peugeot 2008 u1134 error code

[LloydChristmas]

I've got an error code of U1134 coming up on my peugeot 2008 1.6 diesel (2013 year).

I've read that it may have something to do with the stop/start system on the car which hasn't been working for a while, because I assumed I haven't done any long journeys for a long time.

I have a very long journey in the next few days and need advice on whether it's safe to do that journey and also whether you think the long journey will charge the stop/start battery and get rid of the fault.

Sorry if I sound dull I have no idea what I'm doing with cars.

Any help is greatly appreciated.

[GiveMeABreak]

HI

Please pop your VIN up (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). I can then relate the code to the specific vehicle.

[LloydChristmas]

Vin is: VF3**************[VIN obfuscated, can be read by forum staff]

[GiveMeABreak]

Ok, so here is the fault descriptor. Either voltage retention ECU is faulty or the connection to it as it can't be detected (whether intermittently or permanently will depend on if the Stop Start is working intermittently). It will need proper fault finding to tie the fault down, but be cautious of the voltage retaining device as this is a giant capacitor and needs properly discharging before intervention.

The LIN is the Local Interconnect Network and links various components together.

Fault Code:	U1134
Description of Fault:	LIN: Voltage retention device confirmed absent. Faults in communication between ECUs on the LIN.
Conditions for Fault to clear:	Ignition switched on.
Downgrade Modes whilst Fault is active:	Automatic restarting impossible following stopping of the engine (Requires restarting of the engine using the key).
Symptoms:	Problem with automatic restarting of the internal combustion engine Absence of automatic stopping of the internal combustion engine Malfunction of the Stop and Start switch or its LED
Suspect Areas:	Supply of the voltage retention device Reversible alternator supply Electrical harness

[LloydChristmas]

So the description of the error code is 'LIN No communication with the voltage stabilizer.

I plugged my diagnostic box in and can see that the voltage stabilizer is operational, but that is in passive mode, meaning it is not receiving a current.

Does this mean it's to do with the wiring going to the voltage stabilizer?

[GiveMeABreak]

Your code reader is using different terms. The fault descriptor is the official Peugeot fault description for this vehicle. It's called a voltage retention device and it stores the power in a capacitor for the Stop Start system. They have done away with a lot of this technology on later vehicles now.

The symptoms are listed below and could be any of these - obviously if there is a connection / data network issue then then the voltage retention ECU can't communicate with the BSI / Engine ECU and so disables the Stop Start system whilst this fault exists. So you need to investigate the reversible alternator and the supply / harness.

[MelC4]

Hi guys I have the same error on my C4 I have done the checks that Marc said and found corroded pins on the connection to the small wiring harness near the fuse box next to the battery that goes to the voltage retention device & stop start ECU, it was the 12 v red wire to pin on connector 4 stop start ECU had no power and brown wire to pin 10 on connector 3 stop start ECU had a resistance contact cleaner did not work and corrosion was not visible, I take it I still have to get some one to clear the error now. Hope this is a help.

[LloydChristmas]

Hi Mel I'm unable to locate the wiring harness you mention, can you tell me where its located from this picture? Thanks for your help

[MelC4]

Hi your car maybe a bit different mine is a Stop Start C4, the bottom right hand corner of fuse box just inside the wing from the engine bay there should be a 6 wire plug similar size to grey plug on your photo it is heading to your Stop Start ECU above passenger wheel.

[LloydChristmas]

Just in case anyone needs the information in the future, I disconnected the battery and charged it overnight using my father's battery charger and the error codes and service light have gone away

[MelC4]

Is it possible to have a 12v short from Alternator Pin 1 to pin 8 of stop start ECU connection before it connects to ECU ,on Citroen C4. It there a fix for this.

[GiveMeABreak]

@ MelC4: Pop your VIN up, diagrams are vehicle, option and build specific.

[MelC4]

My Vin is VF7**************[VIN obfuscated, can be read by forum staff] can this be the problem that gives me Errors U1133 & U1134.

[GiveMeABreak]

For Fault U1134, see my previous post above:

Here's the other fault code for U1133

Fault Code:	U1133
Description of Fault:	LIN : The reversible alternator is confirmed absent. Faults in communication between ECUs on the LIN.
Conditions for Fault to clear:	Ignition switched on
Downgrade Modes whilst Fault is active:	Automatic restarting impossible following stopping of the engine (Requires restarting of the engine using the key)
Symptoms:	Problem with automatic restarting of the internal combustion engine Absence of automatic stopping of the internal combustion engine
Suspect Areas:	Supply of the voltage retention device Reversible alternator supply Electrical harness

Here's the wiring diagram for the Stop System on your C4:

I have highlighted the Pin 1 wire from the reversible alternator (1021) in red (0010B: multifunction motor ECU NF1 power relay output), which goes to fuse F4 in the engine fusebox. 1012 is the Centralised Voltage Maintaining System.

[MelC4]

Thank you I will check it out.