No electrical power

Red Panda · Post by **Red Panda** » Sat Oct 09, 2021 3:56 pm

Hahaha, it will be etched on my mind for ever. I'll let you know what the final outcome is.

Mike6 · Post by **Mike6** » Sat Oct 09, 2021 4:12 pm

My car was dead but had a fully charged battery showing 14.1v at the charger. Turned out it must have been low on amps. A new battery from 'Tanya' delivered the next day at an unbeatable cost and car was fine again.

Scooba_Steve · Post by **Scooba_Steve** » Sat Oct 09, 2021 4:12 pm

Red Panda wrote: ↑Sat Oct 09, 2021 3:56 pm Hahaha, it will be etched on my mind for ever. I'll let you know what the final outcome is.

At least it's not etched on your nads!

Just had a look at the wiring diagrams. The jump terminal is direct to battery and unfused.

Battery B+ goes direct to F102 40 A and F100 250 A fuses. They are in A400 and are worth checking, I think you've blown the 250 A fuse. Hopefully that hasn't caused any other issues but if none of the A41 (glovebox) fuses have blown then happy days as these are all downstream of the main fuse.

: A400.png (98.69 KiB) Viewed 552 times

ronk · Post by **ronk** » Sat Oct 09, 2021 6:12 pm

With the above in mind - can you do a continuity test from the end of the battery terminals and let us know the results please .

It’s a cheap option than the Fuse change !

Scooba_Steve · Post by **Scooba_Steve** » Sat Oct 09, 2021 6:20 pm

ronk wrote: ↑Sat Oct 09, 2021 6:12 pm With the above in mind - can you do a continuity test from the end of the neg battery lead and an Earth point on the body? Let us know the result please .

It’s a cheap option than the Fuse change !

Not sure how that will prove the fuse on B+. Just test continuity across the fuse

ronk · Post by **ronk** » Sat Oct 09, 2021 6:52 pm

I’ve just realised that was gobbledegook I’d written ((aka crap) amended to say continuity over the leads!

ronk · Post by **ronk** » Sat Oct 09, 2021 6:55 pm

Are main fuses expensive?

I’m surprised the battery charger is still functioning if it’s popped a 250 amp fuse?

Smartbear · Post by **Smartbear** » Sat Oct 09, 2021 7:43 pm

Red Panda wrote: ↑Sat Oct 09, 2021 3:07 pm Thanks for the info. No you have understood exactly. No power anywhere. Very hard to access the battery area also - as the boot is locked as a bonus. Battery is at 13v. I've checked the fuses by the DME relay by the ECU - all good. The battery junction box fuse (the one which is part of the battery terminal connector?) I was thinking must be good as I'm getting 12v when I connect the battery under the bonnet?

If your boot is still closed & you have no access inside it, are the battery terminals still joined together?

Rob

Scooba_Steve · Post by **Scooba_Steve** » Sat Oct 09, 2021 7:54 pm

ronk wrote: ↑Sat Oct 09, 2021 6:55 pm Are main fuses expensive?

I’m surprised the battery charger is still functioning if it’s popped a 250 amp fuse?

I don't think so, maybe £ 50?
Charging/testing from the bonnet terminals would work because it's a big fat lead that just goes straight to the battery (and alternator I think).

ronk · Post by **ronk** » Sat Oct 09, 2021 8:14 pm

I would try and borrow a battery - even if it has to be connected to the existing leads with jump cables.

Red Panda · Post by **Red Panda** » Sat Oct 09, 2021 8:33 pm

Smartbear wrote: ↑Sat Oct 09, 2021 7:43 pm
Red Panda wrote: ↑Sat Oct 09, 2021 3:07 pm Thanks for the info. No you have understood exactly. No power anywhere. Very hard to access the battery area also - as the boot is locked as a bonus. Battery is at 13v. I've checked the fuses by the DME relay by the ECU - all good. The battery junction box fuse (the one which is part of the battery terminal connector?) I was thinking must be good as I'm getting 12v when I connect the battery under the bonnet?
If your boot is still closed & you have no access inside it, are the battery terminals still joined together?
Rob

You have hit the nail on the head Smartbear - now I am in the boot, thanks to Ronk, I can see the 250amp connection is separate. Now connected, all is good. Feel a bit of a dummy, but this forum solved my wayward direction - many thanks.

Mr Tidy · Post by **Mr Tidy** » Sat Oct 09, 2021 8:38 pm

Red Panda wrote: ↑Sat Oct 09, 2021 8:33 pm You have hit the nail on the head Smartbear - now I am in the boot, thanks to Ronk, I can see the 250amp connection is separate. Now connected, all is good. Feel a bit of a dummy, but this forum solved my wayward direction - many thanks.

That's great news.

If it ever happens again stick lump of wood or similar under the bootlid to stop it latching, or use the keyhole in the bottom of the release!

I learnt the hard way with an E46 Compact.

ronk · Post by **ronk** » Sat Oct 09, 2021 9:06 pm

Happy days!

Scubaregs · Post by **Scubaregs** » Sun Oct 10, 2021 6:22 pm

Just a thought Red Panda, you weren’t in the Lebanon the last couple of days by any chance?

I know they are saying they ran out of fuel, but............

https://news.sky.com/story/lebanon-tota ... s-12429825

Steve Conway · Post by **Steve Conway** » Tue Mar 01, 2022 10:54 pm

Battery safety terminal has been activated as the cars electrical system gave out a fault signal when you crossed the leads? Check it out , either it will have blown off the battery or just separated the male female connector inside the plastic housing.
Nothing works other than lights and radio or a similar mix
Had the same problem on mine, positive battery terminal not tightened after I reconnected it after winter, going fast over a bumpy road , all the lights came on on the dash it beeped twice then carried on as normal, checked it out Terminal connector of the battery intermittently caused a electrical volt change, bumpy road computer thinks accident !
Next day nothing no life except radio and lights, re charged battery, all the same, bump started it, drove it for 10 minutes and it overheated no fan!
Checked everything again and the found out about the BST!! Battery safety terminal, checked it out and it’s gone off

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