Member Since: 24 Oct 2007
Location: Oireland
Posts: 4286
Aux battery - dealer disconnect
Away on holidays in the disco recently and no power coming from aux sockets.
Thought it was prob with battery as it’s 4 years old (optima YT 75ah) but on closer inspection, looks like something has been disconnected
Had a new alternator fitted prior to trip so thinking dealer must have not reconnected it. Maybe against their religion or something
Anyhow, the cable doesn’t reach to the battery terminal so must go to pos+ point on part beside battery. Forgive my dumbness, but what is that part?? and safe to connect to there, I presume??
A happy childhood ... is the worst possible preparation for life.
29th Jul 2023 7:27 pm
M3DPO
Member Since: 22 Sep 2010
Location: Notts.
Posts: 8202
Check your fuses first, ISTR there was an upgrade in the size of the auxiliary fuse.
I assume that is the auxiliary battery in the photo, I would not be doing any experiments while on holiday, by the colour of that cable it is earth not positive. I would tape the terminal up till you get home, if it is live from the main battery it should go to a solenoid switch which in turn feeds the auxiliary battery after the main battery is fully charged.It can when others can't,
It will when others won't,
It goes where others don't.
29th Jul 2023 7:59 pm
tanters
Member Since: 24 Oct 2007
Location: Oireland
Posts: 4286
Ok, thanks. So that’s the solenoid switch I’ve circled in green?
That cable comes direct from pos on main battery.
Fitted by TFC about 40 years ago
I’m sure there’s a step by step on what I disconnect/ connect in order? ….. lest I blow something up A happy childhood ... is the worst possible preparation for life.
29th Jul 2023 8:26 pm
Pete K
Member Since: 15 Jan 2016
Location: GL
Posts: 10641
You would think it would goto an empty terminal.
Can’T see under the green circle
Last edited by Pete K on 30th Jul 2023 8:11 am. Edited 1 time in total
29th Jul 2023 8:50 pm
M3DPO
Member Since: 22 Sep 2010
Location: Notts.
Posts: 8202
If the cable comes direct from main battery positive either disconnect it at the battery or tape it up asap, floating about live it is a disaster waiting to happen.
It does look like the ringed item is the solenoid switch, but I can’t be certain, it has been disconnected for some reason, may have been draining the main battery if the solenoid switch is faulty.
If the aux battery is charged you can always use it in an emergency by temporarily connecting it to the main battery positive with the cable in question if it can be made to reach if/when the main battery should go flat which can easily happen by leaving the car doors open.
Check you “cigar lighter” fuses first to get them working, I don’t know which fuse it is off hand but don’t forget the fuses behind the pigeon hole in front of passenger seat and don’t take any out until you have a selection of spares as most likely you will lose one of the little ’s. It can when others can't,
It will when others won't,
It goes where others don't.
30th Jul 2023 7:16 am
tanters
Member Since: 24 Oct 2007
Location: Oireland
Posts: 4286
Ok, thanks for that. Taping it up for now
Looking at length of the cable, it’s measured to go to the solenoid. Deffo wont reach aux battery terminal.
Question now is, can I just connect it at the solenoid or should I disconnect end from main battery - then connect solenoid end and then reconnect at main battery.
I’m thinking there is a safe order to do this ….. and a potentially unsafe order A happy childhood ... is the worst possible preparation for life.
30th Jul 2023 9:43 am
M3DPO
Member Since: 22 Sep 2010
Location: Notts.
Posts: 8202
Have you checked the charge state of the auxiliary battery? Have you got a multi-meter?
The cable has been disconnected for a reason, you need to find this reason, the auxiliary battery may be shot, the solenoid may be stuck closed or open, it may be causing the main battery to go flat overnight if it is drawing current from it.
If everything is good you can just put the cable back on while the car is sleeping( engine off and park brake light out).
What I would do is while the car is sleeping just touch the terminal with the loose wire, if it sparks you have a problem, if it doesn't it may do what it's supposed to do, but there is a risk you may have a flat battery in the morning, hence why I advise leaving it until you get home.It can when others can't,
It will when others won't,
It goes where others don't.
30th Jul 2023 1:25 pm
ronp
Member Since: 29 Nov 2006
Location: North Yorkshire
Posts: 15261
To save you in having to renew the full length of the cable and assuming you’re happy to have that cable connected direct to the + battery, install a busbar (fuse) unit.
Start off with a low amperage, allowing it to blow if there’s an electrical issue.
If not, then fuse at whatever standard rate you are using.
But before doing the above, maybe contact the dealer that disconnected it and ask for their reasoning....... always on the road less travelled 🚧
30th Jul 2023 5:33 pm
tanters
Member Since: 24 Oct 2007
Location: Oireland
Posts: 4286
Thanks Gents
Disconnected main battery, attached secondary cable to solenoid then reconnected mains battery. All seems in order. all the aux sockets working. I think dealer will give me a big fat shoulder shrug but I will ask A happy childhood ... is the worst possible preparation for life.
30th Jul 2023 6:00 pm
KevinD3
Member Since: 05 Aug 2020
Location: Sutton Coldfield
Posts: 1267
Sorry for being the wet blanket guys, but all of the suggestions so far seem to be for tankers to connect a high amp cable that he doesn’t know to something he’s not familiar with on the suggestion of us guys who are making an (educated) guess based on a photo
Best case it gives you your aux sockets back, worst case you’re taking your car home in an urn
Can I suggest a quick phone call to the dealer who did the work and ask him what and why he removed it and where it should go back?
Just a thought 2008 HSE Stornoway Grey
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30th Jul 2023 6:37 pm
tanters
Member Since: 24 Oct 2007
Location: Oireland
Posts: 4286
No mantelpiece in the house so no wish for an Urn
Thanks for concern, Kevin
The dealer will be a bit like and ashtray on a motorbike with this so they won’t know. It’s a TFC installed system which a lot of the guys here would have had back in the day
I must have been out the day they did electrics in skool so never that confident when a prob arises.
There is a cable running from the solenoid to the aux battery. The unconnected cable is the one running from the main battery side to the aux side ….. it’s just hanging there
That cable needs to connect to the solenoid - having searched around, seems solenoid has couple of connecting points. Just need to figure out which one. I connected it to point that also runs to aux battery but I don’t think I’ll be getting an A+ for that …..
I wonder how many TFC aux battery set ups are still driving around amongst this crowd on here ? My kingdom for a good (instructional) photo!A happy childhood ... is the worst possible preparation for life.
30th Jul 2023 10:59 pm
tanters
Member Since: 24 Oct 2007
Location: Oireland
Posts: 4286
Hold the press
Thanks DSL A happy childhood ... is the worst possible preparation for life.
30th Jul 2023 11:02 pm
tanters
Member Since: 24 Oct 2007
Location: Oireland
Posts: 4286
Sorted - cable from solenoid to aux put back in wrong position by dealer - put that to bottom of solenoid. Cable from main battery to top position.
All in order
End of drama A happy childhood ... is the worst possible preparation for life.
31st Jul 2023 2:00 pm
DSL Keeper of the wheelie bin
Member Since: 11 May 2006
Location: Off again! :-)
Posts: 73015
I gathered my techie superpowers were flexed, even while schnoozing in the tub? Or you found a prev thread of mine re third batteries and solenoids? Either way may your beers be chilled and your tech charged.
31st Jul 2023 2:13 pm
Moo D3 Decade
Member Since: 13 Aug 2010
Location: UK
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