[Ian M Davis]

Hello, so I bought a 2017 2l boxer in December and have been converting it over winter, I haven’t been driving it so it has been sat a while but I’ve been ticking it over plenty and it always started straight away no problems.
I ended up draining the battery by accident so replaced it but I had the battery out for a week or so whilst my replacement came (I ordered the wrong one first time oops) now the engine won’t turn over, at first I was getting nothing at all turning the key but I noticed the ecu fuse had blown so I replaced it, now cranks but no start.
it starts with a quick start spray but quickly stops afterwards. I am also getting a continuous buzz from the engine (hard to isolate exactly) even with the ignition off. My side lights are also on continuously when ignition is on but I’m not sure if that’s normal?
I got a guy out to try and diagnose it but after two hours best he could say was maybe probably the immobiliser as we tried everything I’d already tried, plus we got a P0513 code with his swanky snapon diagnostic tool.
I called a key guy up but he said it doesn’t sound like a key problem as it cranks and I can still lock/unlock the van fine and I’ve got no dash lights to say bad key/immobiliser.

Peugeot just told me to bring it in and they can diagnose, but I can’t drive the bloody thing?! plus god knows how much money to push some reset buttons on a screen

any help would be greatly appreciated on how what the hell could be up with it or how I can reset my immobiliser/bsi as I really need this to run but I’m skint

If you Google P0513 it says incorrect immobiliser key which makes a lot sense. The immobiliser locks ECU so the vehicle will crank but the injectors will not fire.

The immobiliser is built in to the ECU and BSI. If the battery runs flat or is disconnected while the BSI is awake it can corrupt or completely wipes the BSI. When you say you can unlock the van with the key do the remote buttons work? If they do there is a chance the BSI is okay.

I understand that the immobiliser light is going out which is what page 18 of the 2017 Boxer handbook said should happen (see attachment). I understand a fuse associated with ECU blew so the problem may be with the ECU part of the immobiliser. The only way to determine this is with a Peugeot diagnostic tool. Given that you can't move the van it may be worth considering buying a good Chinese clone of Peugeot tool they are not that expensive and many forum member own them but you need a suitable laptop.

Your simplest solution is to try and find a replacement ECU kit consisting of the ECU, BSI and key PCB from donor vehicle. Alternatively some automotive locksmiths know a lot about immobiliser so may be able to sort out your BSI or ECU.

 

[Ian M Davis]

thank you for some insights, yeh I had googled that but when I told all my symptoms to the auto key specialist he said otherwise so I took his opinion as probably better than mine, as he said it simply wouldn’t crank if it was the keys, but then another Peugeot guy said it would? aaahhhh

There is a chance Fiat/Peugeot changed the electrical design for your model of the Boxer. I can't access the wiring diagrams for your Boxer but on the previous model the ignition switch directly controlled a relay which provide power to the starter motor solenoid. On all Peugeot cars I have looked at they will still crank if the immobiliser has locked the ECU.

 

[Ian M Davis]

There is an easy was to check if the transponder stops the van from cranking. On later model keys the immobiliser transponder and remote entry transmitter are on the keys printed circuit board. In most keys it is possible to remove the circuit board from the key case. Hence, I suggest you remove the printed circuit board from your key and see if the car still cranks. My bet is it will still crank.

Note on early model vehicles the key had two parts: a small black chip in the corner of the key case and a PCB for remote locking. The small black chip was the transponder but on later keys they integrated the transponder in to a chip on the PCB.

 

[Ian M Davis]

One question. The fuses should be numbered do you know the number of the fuse you replaced. No 18?

 

[Ian M Davis]

Wait so if I do this, what information is this giving me? If it still cranks then it’s not a key problem? Or it is a key problem?

No it will tell you if the immobiliser inhibits the starter motor. It will also tell you if the dash immobiliser light is working. With the PCB removed and the ignition on the light should stay on.

Have you checked any other fuses in the engine fuse box? The ECU should have more than one power connection often via fuse 22. It is quite common for Peugeot not to list the function of all fuses.

 

[Ian M Davis]

I’ve got it running with Easy start though so it’s not a starter motor issue, just fuel injection (I think), the engine cuts out as soon as you stop spraying, which is what I assume the immobiliser does?
I was struggling to get at any other fuses as they’re a pig to get to without taking it all out, not sure if I’m that brave or not, a professional tinkerer but I have some limits. But I’ll try and check 22.

I agree the immobiliser should shut down the injectors. For the immobiliser to work the key needs to match the data stored in the BSI and ECU. I suspect the problem is with the ECU but the key cut guy was claiming the immobiliser was good because the starter motor was working. I just wanted to demonstrate that he is wrong.

 

[Ian M Davis]

I agree the blown fuse and the buzzing are the real issues. You may have been getting a immobiliser fault code from the SnapOn tool because of an issue with the ECU. I suspect more than one fuse has blown. My worry is why the fuse blew.

 

[Ian M Davis]

Thanks for the update.

I looked at the wiring for a Boxer with a Euro 5 engine which is likely to be similar to the later Euro 6 engine. Fuse 18 only provides power to the coil of a relay in the fusebox. This relay is controlled by the ECU and provides power to a lot of services including a main power line for the ECU.

I think this fuse was responsible for the P0531 code your first visitor got with the SnapOn tool. I think the code is now "historical". Unless you clear a code with a diagnostic tool it will take several starts to auto clear. However, it is probably why everyone blames the key.

The starter motor solenoid is controlled by a relay which is operated by the ECU. Fuse 18 is not shown in the starting wiring diagram which implies it should not affect the starter motor but I think that is just an oversight. The ECU needs fuse 18 to work properly.

With regard to the buzzing there are several things with a permanent battery connection:
(i) Alternator
(ii) Starter motor
(iii) BSI
(iv) ABS/ESP (via fuse 1 and 23)
(v) Glow plug relay (via fuse 2)
The glow plug relay should only close when the ignition is on. However, these relays often have problems so I wonder if it's stuck in the closed position. If you want to investigate that you could remove fuse 2 and see if the buzzing stops.

 

[Ian M Davis]

Wow, thank you so much. I will go and try that later on
the ringing/buzzing is coming pretty much directly from the engine though, which makes me think it’s not a relay


Unfortunately I tried that and checked every fuse again but still this ringing persists, hopefully tomorrow these two guys can figure it out as it’s getting pretty disheartening

Okay good luck with your next team hopefully they can sort it out.

BTW If there is a problem with the glow plug system you need to leave fuse 2 out. This will not stop the van from starting.

 

[Ian M Davis]

He tested a few fuses and noticed how some are reading battery voltage on the live side but then are reading 2-8volts on the other?! .

I think what he means that there is full battery voltage in parts of the fuse box but only 8V at other parts. The only way you would get 12V on one side of a fuse and 8V on the other side is if the fuse is blown. Many fuses are relay controlled and the various modules throughout the van have multiple power connections so 8V at a fuse that is turned off is possible.

It sounds like the BSI and key are communicating okay but there is no communication between the BSI and ECU. These are connected via computer bus called a CAN bus. In most cases if you unplug the ABS it disconnects the CAN bus link between the BSI and ECU. it would be worth checking the ABS connector. Is there any chance water has got in the ABS connector? That often stops the CAN bus from working.

I am still wondering about the sound you are getting. Could it be from the ABS pump. There is usually three battery connection to the ABS. Two of these are on all the time. The other is to the ABS controller. The ABS pump shouldn't be running but if there is something wrong with its controller it would explain a lot.

If you want to have a go yourself and have access to a multimeter I should be able to guide you through.

 

[Ian M Davis]

Yeh sorry that wasn’t the clearest of explanations. I meant he noticed when he pulled out a couple of the fuses and tested the female ports, one side was hot but so was the other one.

That doesn't surprise me. Several devices have multiple power lines and you often find there is floating voltage.

I have sent you a PM.

 

[Ian M Davis]

One easy check to is measure the resistance of the main CAN bus. It looks like the van has the conventional diagnostic connection so we should be able to do this at the diagnostic connector.

The first thing to do is disconnect the battery. Remember to follow the 3 minute rule. Everything need to be off and the key removed, drivers window open for access if possible, doors shut (not locked) and then wait at least 3 minutes before disconnecting the battery.

Then put the multimeter on the Ohms scale (Ω) and measure the resistance between pins 6 and 14 of the OBD connector. It should read 60 Ohms but if it reads 120 Ohms it means the ECU is not connected.

 

[Ian M Davis]

When car batteries run flat it can corrupt the electronics. This may be why the guy rewrote the ECU. It is more common for this to corrupt the BSI. Removing fuse 18 may have rebooted the ECU.

I have looked through the wiring diagrams for your van and there is also another important ECU fuse - Fuse 16 which is not listed in some documentation. This fuse provides a second power supply to the ECU when the ignition is ON. Fuses usually have bare piece of metal showing on both sides of the fuse. This is a convenient place to measure voltage with the fuse in place. Are you able to turn the ignition ON and check the voltage on both sides of fuse 16. It would also be worth checking it with the ignition OFF.

The last people who worked on the van my have done this but it might be worth doing a full reboot of the whole the whole system. This link will take you a set of reboot instructions.

https://www.frenchcarforum.co.uk/forum/viewtopic.php?f=51&t=61997

One other test worth doing is remove fuse 18 again and see if the engine noise stops. If it stops there may be a faulty relay in the fuse/relay box at the front left of the engine compartment.