I have now received replies from both the Market Surveillance Unit (MSU) at VOSA and the International Standards Service (IVS) at the DfT.
The gentleman at the MSU has said the following:
Thank you for your patience while I consulted with colleagues and researched the vehicle.
Initially, I believed that the parking lights would operate when the ignition is switched off, as this has been the case with every vehicle I have owned over the past forty years. However, after reviewing the relevant lighting regulations, I found no requirement specifying that the parking lights must illuminate without the ignition being engaged. It appears, therefore, that the vehicle meets type approval standards.
I suggest directing your query to the VCA for further clarification, and I will update you should any additional information become available.
The view of the MSU is consistent with that of Ineos therefore that there is no enforceable requirement for the obligatory front and rear position lights to work when the ignition is off. I have responded by asking for clarity about the legal situation should someone have no option but to leave a vehicle at the roadside after dark (although realistically I do not expect a legal view from the MSU) but have also asked how it is that at the time that the RVLR were drafted the risk of an unlit vehicle at the roadside was considered so significant that lights were essential yet today, when there is far more traffic and traffic speeds are higher (and headlights have ben weaponised) the risk is no longer considered significant by the EC and consequently the UK. If I get a reply I shall share it here.
The IVS has responded as follows:
Thank you for taking the time to contact the Department for Transport about road vehicle lighting.
As you highlight there is a difference in the requirements in UNECE Regulation 48 and the Road Vehicles Lighting Regulations 1989 as amended (RVLR). We would like to assure that vehicles that fully comply with UNECE regulation 48 are legal to use on UK roads and based on the information supplied we consider it unlikely that this is a compliance issue, although you have identified that the configuration of the INEOS lighting system is such that you are not able to securely leave the vehicle unattended with the front and rear position lamps activated, which has implications for where you can park the vehicle. However, in such situations where it is necessary to inform other road users of temporary obstruction when the vehicle is at rest it is permissible to utilise the hazard warning device, which according to the published Grenadier owner’s manual remains active when the ignition is deactivated.
Based on the information supplied we assume that the vehicle was not approved with parking lamp functionality so the paragraphs 6.12 of regulation are not relevant as they are optional lamps and are not fitted to the Grenadier. Unfortunately, page 69 of the published Grenadier owner’s manual suggests otherwise, it may merely be translation error as we believe it should potentially read position lamps / side lights.
Once again this confirms Ineos's view that the position lamps do not need to operate on a parked vehicle in order for the vehicle to be fully compliant with EC (and hence UK) legislation, however daft that might seem. It is interesting that the IVS comments about the permissibility of using hazard lights rather than position lamps since this, again, is not wholly in accordance with pre-existing UK legislation. This is, I suppose, the result of the EC calling the shots and despite Brexit the UK has failed to keep up.
It would be interesting to know how many other makes of vehicle have the same inability as the Grenadier to illuminate the parking lights - my unscientific survey amongst quite a large number of co-workers who drive about 15 different makes of vehicle has not so far revealed a single case - and it may be that a letter to the senior management in Ineos might be worth a shot. Failing that, just be careful where you leave your Grenadier and keep your fingers crossed that it does not take a terrible and tragic accident involving an unlit Grenadier to sway public opinion.