Citroen Spacetourer code B1805:62 Starter Fault - Consistency

[MonsieurM]

Hi all,
I have a Citroen Spacetourer 2017 passenger van which keeps returning the code B1805:62 Starter Fault - Consistency. The issue is that this code seems to prevent the vehicle from doing its own DPF regens and therefore in short time the particle warning light/message will come on, then the DPF will start to clog and that will trigger limp mode.

Can anyone provide more details on code B1805:62? I'm struggling to find further information on it. The van has no issues starting.

TIA
VIN VF7**************[VIN obfuscated, can be read by forum staff]

[GiveMeABreak]

Unfortunately this is non-specifically characterised fault, so could be multiple systems causing it, but here is the descriptor code for you:

Fault Code:	B1805 62
Description of Fault:	Starter motor fault: Not characterised. The drop in voltage linked to the activation of the starter motor does not occur (Drop in voltage greater than 1,5 V). The time of appearance of the fault code is 1,5s Conditions of activation of the diagnostics: BSI triggered.
Conditions for Fault to clear:	Drop in battery voltage during the starting phase, less than 1,5 Volts
Downgrade Modes whilst Fault is active:	-
Symptoms:	Starting problem
Suspect Areas:	Configuration of the BSI Configuration of the engine management ECU Starter control interface unit protection fuses (*) Starter control protection fuse (*) Built-in systems interface connector Engine management ECU connector Starter control interface unit connector (*) Engine fuse box connector (*) Ignition switch connector Gearbox ECU connector (*) Electrical harness Starter control interface unit supply (*) Ignition switch Starter motor Starter control interface unit (*) Engine fuse and relay box(*) Engine fuse box (*) Gearbox ECU (*) Built-in systems interface Engine management ECU