New fault code P0405 help please

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Benscab123
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New fault code P0405 help please

Post by Benscab123 »

Started the car today and immediately came up with engine fault , plugged my ultra expensive (£20) code reader in and got P0405. Any ideas on a fix please ?
Thanks.

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GiveMeABreak
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Re: New fault code P0405 help please

Post by GiveMeABreak »

Have a look at the fault in my post here:

viewtopic.php?p=617446#p617446

It is a slightly different engine, but I have checked he fault against your Picasso and the fault is the same (so will save me posting it up here again).

Benscab123
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Re: New fault code P0405 help please

Post by Benscab123 »

Sorry Marc, but after reading that post I’m still no wiser, are you saying the fault is with the ecu ?

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GiveMeABreak
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Re: New fault code P0405 help please

Post by GiveMeABreak »

The ECU is reporting that the voltage for the EGR copy position signal is too low. So if you read the parameters with Diagbox, I suspect that whilst this fault is active it will show the EGR OCR as 0% and also the copy position as 0% as it says in the post. So you need to check the supply voltage to the EGR (which is a shared 5V supply) from the engine ECU.

If I haven't already provided you with a diagram of the injection circuit in a previous post (I can't remember as I do so many similar ones), let me know and I'll post one up here that may help you trace the wires to check and test.

Benscab123
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Re: New fault code P0405 help please

Post by Benscab123 »

I don’t recall seeing a diagram Marc, sounds like something I’ll have to pass on to a trained professional though. Sounds a bit too technical for me.

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GiveMeABreak
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Re: New fault code P0405 help please

Post by GiveMeABreak »

Ok, so basically this is telling you that the there is an under-voltage situation with the EGR Sensor.

Here is the internals of the EGR
C4 Pic EGR B.PNG
C4 Pic EGR B.PNG (84.39 KiB) Viewed 137 times
Key
ReferenceDesignation
eExhaust gas outlet to the exhaust gas recycling (EGR) heat exchanger
fExhaust gas inlet
17EGR electrovalve valve
18Helicoid ramp
19EGR electrovalve valve position copy sensor
20Electric motor

Here is an enlargement of the EGR solenoid connector
C4 Pic EGR.PNG
The engine ECU supplies voltage to the EGR solenoid valve potentiometer on pins (5) & (1). The otor is supplied by pins (2) & (3), and the copy position sensor is on pin (4).

Pin (1) 1310: "EGR" solenoid valve potentiometer supply
Pin (2) 1372: Throttle motor command by -
Pin (3) 1371: Throttle motor command by +

Pin (4) 1346: Exhaust gas recycling solenoid valve repeat sensor signal
Pin (5) 1319: EGR solenoid valve potentiometer earth

Below is the larger diagram on which you can see the 5 pin Black EGR connector (1297) with the wiring connections I have mentioned above. The engine ECU is shown as 1320. Connections from the EGR plug (1297) go to 2 different connectors on the engine ECU: Pins (5) and (4) go to the 32 Pin Grey Socket and Pins (1), (2) & (3) go to the 48 Pin Brown connector.

So I would get your auto electrician to test the circuits accordingly - and also check that the actual pins in the sockets have not retracted and are making good contact. Check for shorts in the plugs and or on the wiring between the EGR wiring plug and the 2 plugs of the engine ECU that these connections go to.

Main Injection Diagram for the C4 Picasso DV6TED4

Image

moizeau
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Re: New fault code P0405 help please

Post by moizeau »

This was the same code I had. The egr was knackered. You need to plug it in to Diagbox and do an actuator test. Also in Diagbox you'll probably find a number of faults that your reader isn't detecting.
Have a read here
https://www.frenchcarforum.co.uk/forum/ ... hp?t=64723

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GiveMeABreak
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Re: New fault code P0405 help please

Post by GiveMeABreak »

..... which is listed as a possible suspect component on the fault code report. So electrical or the EGR itself. But easiest way is to at least attempt a check of the wiring and plugs first.

Benscab123
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Re: New fault code P0405 help please

Post by Benscab123 »

Thanks guys, this morning I have brand new codes 😂. P0489, P1162 and also the dash flashed up esp/asr fault and faulty parking brake.

Seems every time I rectify one fault another shows up, this car needs to go !!

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Re: New fault code P0405 help please

Post by moizeau »

You really need it diagnosed properly otherwise you'll find yourself chasing red herrings. As you will have seen in the post that I linked there were some strange ones like 'clutch torque'. The proper diagnostic kit also allows you to check various components and not just swap things out. My van had caused Rich loads of trouble, but with the correct bit of kit it was a much easier fix than expected. I may have been lucky. There is a link somewhere on here that lists people who have access to Diagbox / Lexia / PP2000, it may not be an up to date list and some of the people may be dormant but it's got to be worth a couple of PMs.

Benscab123
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Re: New fault code P0405 help please

Post by Benscab123 »

Thanks, I have someone local who has diagbox so I’ll get it plugged in ASAP, just thought someone on here might have come across this before.

Benscab123
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Re: New fault code P0405 help please

Post by Benscab123 »

So, plugged the car into diagbox and here’s the results (not a bloody clue what any of it means by the way apart from The sidelight bulb).
Looks like the pics have loaded in reverse order so best to start from the bottom 😂😂
Attachments
F843986F-CE6F-497E-A9B7-594799F445FF.jpeg
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0A885D1E-B92B-4A32-9140-2C32EA29E04D.jpeg
A4995D2C-FF3E-4A9D-9570-5B060DCFF8A4.jpeg
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4CFC0CDA-9ACA-4AF1-B0FA-8707B85418BB.jpeg
67557AAF-CBA8-46FE-BFBC-623AC5F16552.jpeg
3D01E521-D052-4B12-85D7-1CACA85B2F4E.jpeg
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FE1BCDB7-315C-4DC9-AF9A-7AE11D4ED61C.jpeg
1E5A5A15-9B1B-456E-A050-36FA0ABD2A7F.jpeg
0B0E4DE5-F8E1-4D71-99C6-55B27F65062A.jpeg
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644CDABD-573A-48DB-93F8-F6CEECEFB141.jpeg
979A157F-1FC8-42F4-BB6D-9C372000733E.jpeg
A7725D94-0438-4624-849D-C346B08F98D3.jpeg
2F7DDC1B-4130-4FCB-80C4-252E8175D8C5.jpeg
533AE9E6-4D85-40C2-AC3A-6B3367FC3027.jpeg
DCF70569-2AB3-4B17-9D44-75F10FD3790E.jpeg
018406B5-226D-40C8-B3C8-CF1B245140C6.jpeg
A2CBB978-149F-41D1-8225-2082CEBD914A.jpeg

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GiveMeABreak
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Re: New fault code P0405 help please

Post by GiveMeABreak »

Not being funny or anything, but not much of that is going to help unfortunately as from the last picture you would seem to have 9 engine ECU faults - and the rest of the screenshots are not very helpful as some of these are missing the fault code, so we don't know to which of the 9 faults they relate to... I can just about make out a few codes....

A list of the 9 engine ECU individual fault codes would suffice initially so we can see what they all are.
Ditto for the 2 gearbox faults and the ABS fault.

It would seem you have a few issues going on here...

It's not unknown on these C4 Picassos for the dense wiring loom to the left and under the engine fuse box to have a few broken wires as a result of the weight and tightness of the wiring bundle causing strain on some of the thin wires. I can't say this is what has happened in your case, but it is a possibility with so many problems.

I'll try and dig a video I saw of this issue and post it up.

On looking further I can see make out the following faults codes, so will put these up in a while, apart from the P0405 that I've already done for you in my last post.

moizeau
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Re: New fault code P0405 help please

Post by moizeau »

There seem be a few duplicates there. Valve stuck, open too far etc. Note the codes on a piece of paper along with a brief description (see my post previously linked), delete all faults then rescan. See what comes back. If you click on the injector ecu it will bring up another menu, from there you can do an 'actuator test'. Electric EGR along with 'throttle egr' will be listed. Click on those and see if you can hear a clicking. If not check 5v to the egr pin Marc listed (ignition on, engine off). That will tell you if power is getting to the valve, if nothing is happening after that, look at the valve. Much of this was mentioned in my post.

Benscab123
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Re: New fault code P0405 help please

Post by Benscab123 »

The codes are as follows:
P0483
P1728
P0489
P1162
P0405
P1459
P0490
P0409
P0401
P1755
U1208