OV9

Just became aware of these gadgets via a discussion on the Lotus forum - you lose info on the Alpine head unit when you change the 12V battery on the Evora, and it also briefly sets the alarm off when you connect a new battery : which I never remember, hence it usually causes me to pit my shants.

Anyone got one of this gadget malarkies already? Any advice?

Longer leads seems sensible, but this one gives the option of just using 8x AA batteries - which seems pretty practical. Any obvious downsides I am missing? (obviously I wouldn't expect to leave any car on AA's for days - just for the couple of mintues between 12V battery swaps.

I've been using one for years, a very handy gadget.

As Ian inline fuse holder with current display, to test for current draws with the engine off etc.

Dave!

XJ needed one because JLR can’t design electronics. I didn’t have one so just put a jump back instead and replaced battery as normal. It worked.

V8Granite wrote: Thu Mar 05, 2026 9:42 am I've been using one for years, a very handy gadget.

As Ian inline fuse holder with current display, to test for current draws with the engine off etc.

Dave!

I’m pretty sure you have a typo in there (unless you name your tools ) but I think I get what you mean - any pics / specs for your setup?

Using a pair of jump leads and another battery/car is the way I've seen it done.

Does the one you've linked attempt to power the car's battery from the OBD port?

Jobbo wrote: Thu Mar 05, 2026 9:50 am
Does the one you've linked attempt to power the car's battery from the OBD port?

No - it powers the "at rest" vehicle electronics requirements via the OBD port (which allows you to swap the car battery without losing any info / resetting the ECU / causing the car to freak out in any unexpected ways).

Jobbo wrote: Thu Mar 05, 2026 9:50 am Using a pair of jump leads and another battery/car is the way I've seen it done.

Does the one you've linked attempt to power the car's battery from the OBD port?

On the ML you can't get jump leads on and re-fit and remove the battery u less you take the seat out. It was the reason I bought one.

This is Ian Mik

https://www.amazon.co.uk/Sealey-TA120-A ... d_source=1

Maybe I'm too poor to have this problem, but I've never had a battery swap that hasn't just required a few mins driving to reset everything, or re-entering a radio code (for those old enough to remember that).

Even the Evora just fixed itself after the battery died....I think the worst thing was windows needed to "remember" their location.

I think your ‘vora had a different head unit (?)

Mine remembers radio presets etc but loses all the tone info and latency settings shizzle (and the tone settings are all sweepable parametrics which are a right PITA to set up).

When I had an early-life-failure battery, the repeated low-voltage readings caused the airbag light to come on (and the airbags to be deactivated) - which required resetting by the specialist. I’ve heard of others facing this issue after a battery swap, so keen to avoid that.

Are you fitting a CarPlay head unit like I told you to do?

scotta wrote: Thu Mar 05, 2026 12:16 pm Are you fitting a CarPlay head unit like I told you to do?

No