B9 engine fuse box (PSF1 / BSM) wiring

[jthyttin]

Hi,
as instructed in another thread I will start a fresh one under proper subforum. The car in question is 2016 Partner 1.6 BlueHDI 100, but I believe this is more B9 specific than version specific. PSA will never cease to surprise, so happy to provide VIN by PM is somebody is willing to help.

https://www.berlingoforum.com/thread-19801.html

Quick update, R8 is indeed shown as being inside PSF1, the engine bay fusebox. There is a fuse F8 which is "Starter Relay" on the same fusebox. This powers the circuit going to the starter relay R8 contacts, and from there on to the starter solenoid terminal.

At minimum I'd like to know, which connector and wire in the fuse box is going from R8 to starter solenoid? Wiring diagram would be greatly appreciated (if it's human readable, I suspect everything from PSA isn't...)

Since R8 is buried inside the sealed fuse box (PCB covered in protective goo), finding the right leads for measurement would be a destructive action. Haven't tried to disassemble the fuse box, but watched few videos of people doing so.

I already tested connectivity from plug at starter solenoid, to all large and midsize pins in fuse box connectors to no avail. Don't want to damage the small pins on the connector side, and I don't believe they used the small pins for solenoid wire.

So I believe there's something between R8 output and starter solenoid (rather than straight wire) that makes it impossible to use simple connectivity test (not diode, I tried it both ways). Don't want to mess with ignition switch etc. at this point. My goal is to use the wire from R8 to directly feed 12v to solenoide for starting. Don't ask why...

[Sol]

Best I can do is the schematics for engine start on the B9, and the component numbering data. 

Traditionally Citroen do not show their relay locations even in ServiceBox. We have no access to anything better than this.

Wire 100, pin 2 of a 5 pin plug coloured yellow. (100/2 5VJN) is the output from the relay. F8 is the feed to the relay contact common.

According to the workshop schematics, it's a straight wire to the socket 5V JN from R8 contact, and also from that plug to the starter.

[jthyttin]

Thanks for the PDFs they're definitely human readable and what I can see correspond 100% to Peugeot (which shouldn't be a surprise).

But there's no connection between the pin on fuse box connector and the solenoid plug. I'm quite sure the wire is fine, the motor is low mileage and if I take out the solenoid plug, car diagnostics and Diagbox will immediately complain about missing starter.

Now that I know the wire, I think I reassemble the PSF1/BSM thingy and test the connection with ignition on. But that will have to wait until I have more time.

[jthyttin]

Forgot to update, in case somebody else has similar problem.

The wire from 100 / 2 5VJN doesn't go directly to starter solenoid in my LHD 2016 Partner 1.6 BlueHDI 100. It's also quite thin. I suspect there's secondary relay or similar arrangement, since the wire disappears to the wiring loom along with another thicker pink wire.

I assume both wires go to relay, and thicker wire feeds 12V back to the BSM/PSF1 location where there's connector near the fusebox and the same thick pink wire finally goes to the starter solenoid. Since I identified the pink wire I didn't rip the loom open, just used the pink wire that goes to the starter solenoid.

[Sol]

Good result, thanks for posting back. There are gaps in the Citroen documentation, but it's the best available I'm afraid.