Intermittent Starting and Electrical Failure on 2004 Citroën C4 1.6 HDI (92 hp)

[yerbito]

Hi everyone,

I’m having a problem with my mother’s 2004 Citroën C4 1.6 HDI (92 hp) with around 100,000 km. For about a month now, the car starts only sometimes. When turning the key, the car can appear completely “dead.”

At first, I thought it was the battery, but it’s not completely bad—it’s around 70% of its useful life. It should deliver 540 Ah when starting but gives about 480 Ah. I disconnected and reconnected it several times, but the problem persisted. One time, I left the key in the ignition while reconnecting the battery, and the relays clicked; the car started and worked normally.

However, it doesn’t always start properly. Sometimes it runs fine for a day or two, then the issue comes back. To “revive” it, we reconnect the battery with the ignition on. In some cases, after this, the wipers stay on, the RPM and speedometer don’t show anything, the total km and fuel gauge don’t work, lights and windows don’t respond, and even if you remove the key, the car doesn’t turn off. After a while, it shuts down as if you had turned off the ignition, without any jerks, and independently of the key.

I read that this could be a grounding issue, so I checked the battery grounds, but they weren’t corroded. I also read that the problem could be the BSM or PSF1, so I got a second-hand BSM (L04-00) that supposedly works, but the car behaves the same. I noticed at a salvage yard that almost all of these units are removed, so they must fail often. Therefore, I doubt the one I got is fully reliable.

Another possibility is the BSI, but it needs cloning, and I don’t have the means to do it.

Has anyone experienced something similar and can give me advice on how to solve this problem?

Thanks a lot in advance!

[mickthemaverick]

The first thing to do is a proper BSI reset following the procedure in the link below and then see how it behaves. The next step if still troublesome will be a global scan with Diagbox or similar high end diagnostic tester. https://frenchcarforum.co.uk/forum/view ... 79#p601679

[yerbito]

Ok. Thanks so much.
Tomorrow I’ll try to do that reset, but after reconnecting the battery the car is dead and only comes back to life when the battery is connected with some load (ignition on). Nevertheless, I’ll try to follow that tutorial to see what happens. I tried a simpler reset by pulling the light and indicator stalks with the door open and the brake pedal pressed, but the horn never sounded. Maybe I wasn’t doing it correctly. Diagnosed with Diagbox, it gave error P1351 (glow plugs) and U1118, U1308, and U1318.

[mickthemaverick]

Those three U codes are all similar in that they suggest you are having communication issues in the system. I'd suggest before doing the BSI reset go through the engine fusebox making sure that all the fuses are clean and there is no corrosion in any of the plugs. Once you are happy that is the case then do the reset.

[yerbito]

Those three U codes are all similar in that they suggest you are having communication issues in the system. I'd suggest before doing the BSI reset go through the engine fusebox making sure that all the fuses are clean and there is no corrosion in any of the plugs. Once you are happy that is the case then do the reset.

All the fuses in the engine compartment fuse box are fine, or at least none are blown. I checked them with a tester, although to be honest I didn’t remove them, but I will. I only took out the maxi-fuses, and one of them looked bad (it was black), so I replaced it, but it’s for the electric fan.

I tried to do the reset, but nothing happened; maybe I did it wrong. Here’s how I did it. The car is “dead” before starting, that I confirmed.

I removed the key from the car (it has no remote) and disconnected the negative terminal with the car closed. After a little more than 5 minutes, I reconnected the negative terminal. I waited 3 minutes or a bit more, turned on the parking lights, and from the window, I put the key in the ignition, but the car stayed dead.

Even so, I tried opening and closing the doors using the driver’s door lock. I did this several times, then tried to turn the ignition again, but nothing happened. I removed the key again, disconnected the battery, waited 5 seconds, and reconnected it. I tried to turn the ignition, but the car was still dead.

I left the key in the ignition and disconnected the battery again for about 5 seconds. When I reconnected it, the relays clicked and everything worked, and the car started without problems.

Does anyone know what the two central BSM wires are for? One of them looks bad.

I checked the gearbox ground, the cable that goes from there to under the battery, also the ground on the fender near the left headlight, and the one under the glow plug relay. All of them were fine.

But there is one mentioned on the internet, the M0283, which is supposed to be near the brake servo and the windshield wiper motor, and I can’t find it. Does anyone know where it is?

Thanks.

[yerbito]

Yesterday I discovered that if I switch the BSI to workshop mode, the car never dies and always starts fine. As soon as I switch it back to normal mode (customer mode), the car dies again. I’m starting to think the BSI is faulty.

[yerbito]

Would anyone have the wiring diagrams for the BSI and BCM in the photos? I’d like to check that they always receive proper 12V. Thanks.

[yerbito]

Hello everyone,

Just a quick feedback to close the topic and to thank you all for your replies.

The issue was indeed related to the BSI. I had the BSI cloned, and now the car starts perfectly and never goes completely “dead” anymore.

During diagnosis:
– I disconnected the instrument cluster.
– I installed another BSI for testing, and in that setup the car no longer shut down or went dead.
– This clearly pointed to an internal fault in the original BSI, which led me to cloning it.

I was also given the PIN code.

Thanks again to everyone for the help and suggestions, they were really useful.