Talk Morgan Forums Morgan Sports Cars Morgan Plus Four, Supersport & Plus Six (CX & CXV Generation Vehicles) Overseer warning light

I have an intermittent overseer warning light showing occasionally, normally after 30 - 40 minutes of driving. Once the car cools down it doesn not show again for another half an hour. I don't have time to get it reset by my local dealer before leaving for 10 days of continental touring, probably 1,500 miles or so.

My car is a 2025 MY 2 litre Plus Four and as far as I can gather these devices are fitted to stop unintended acceleration, mainly on autos.


Does anyone know if it will be OK to leave it without a reset for my trip or is it something I can reset myself, such as depressing a button?

Is yours a manual? Mine is & I still got the light when trying to start the car. It turned out to be a faulty 12v battery.
There is a switch under the dash on the drivers side you push to turn it off. I couldn't make that work nor would an OBDII reader remove it. A new battery solved it.

Is your battery maybe on the way out? Modern ones can fail without warning & mine was 18 months old. The AA man said that wasn't unusual.
Can you put it on conditioner & then test it?

Later cars (mine’s a model year 23) don’t have the Overseer cut off switch, but still have the Overseer. If you’re driving normally and it’s coming on either, as John said, the battery is at fault (but why would it be if the car starts normally and you’ve been driving for some time recharging the battery), the sensor has a fault or, perhaps, there’s an issue with a connection.

Test the battery! Both Halfords and Kwik fit will test your battery and give you a print out FOC.

The overseer warning light showed on my 2025 Plus Four (auto) after about 600 miles from new - came on and stayed on for a couple of days then cleared. At the 1000 mile service / inspection, the mechanic recalibrated the overseer (sensors, I think) and told me that if it comes on again, just to ignore it. It has not done so since.

Thanks to you all and a good point about the battery John, and yes, it is a manual. It was new about 16 months ago and always starts the engine with alacrity, however, to save having to put it onto a CTEK every week, I have fitted a battery cut off switch which completely disconnects the battery and which I use every time I park up for more than a couple of days. I wonder if this is upsetting the overseer, although it is odd that it takes 30 minutes or so to wake up? Everything else resumes where it left off.

I'm thinking I might just ignore it for the next 1500 miles or so, as everything else works fine when it is showing. Bad thought?

I'd be inclined to this line of thought. If you are cutting power to all the systems of the car, there is a likelihood that the systems that expect to have a constant feed of power (for example the CAN bus), albeit limited, will be confused by the on/off of a kill switch. It would create similar, but worse, issues to those mentioned by people questioning a failing battery.

That’s a possibility, but I should mention that when I had an issue with my Bluetooth module failing to connect to my phone the MMC sticking plaster solution was to disconnect the battery for 10 minutes. There were no subsequent issues post reconnection of the battery. However could days of power loss be different to a few minutes?

I would not be disconnecting my battery so often, the systems will be constantly rebooting and we are talking Morgan / BMW software I would be expecting a glitch or two over time. Much better to go back to using the CTEC.

I use ctek comfort plug permantly wired to the battery