On 15/06/2020 13:27, Smolley wrote:
On Sun, 14 Jun 2020 20:48:54 +0100, Dave Liquorice wrote:

On Sun, 14 Jun 2020 11:47:38 +0100, Jim GM4DHJ ... wrote:

https://www.ebay.co.uk/itm/OBD2-Auto...Saver-OBD-12V-
Battery-Replace-Tool-Extended-Cable/292763616836?ssPageName=
STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

anybody use one of these ?...are they safe?

Donno, I just made up a open end to lighter plug made sure the lighter
socket was powered and connected a 12 V SLA to the open ends.
With a modern car one might have to be quick changing the main battery
as they have a habit of going to sleep after a while and might switch
off the lighter socket...

I guess the ODBII power line is less likely to be turned off. Or find
other unswitced/secure +V and Gnd points, obvoious place is the around
the battery terminals but there is a chnace that one connection might
get dislodged whilst faffing about with the battery...


My car started and ran ok after removing the battery for a couple of
weeks, must have non volatile memory in the ECU.
.


Only thing my old freelander needed was radio recoding

Only time I have heard of a car failing to go after a battery
disconnection is when a major sensor array has been replaced as part of
a service. Some parts are manufacturer specific unless you know the magic.



--
Labour - a bunch of rich people convincing poor people to vote for rich
people by telling poor people that "other" rich people are the reason
they are poor.

Peter Thompson