Hi guys, I have foolishly connected a new battery the wrong way round in my 3.6 L322! It briefly beeped and sparked but now I can’t start it. Lights, wipers etc all work. I’ve done some reading, possible alternator issue, all fuses in the glove box are fine
Is there a phyro fuse on the positive cable that has fired to protect things? Is there a way to bypass it to check?
I blame man flu and impatience! I’ve only had the car a few days so I am new to these.
Really appreciate any help! Thanks

Hi,

I did a search on here for battery fuse…. I knew I’d read of one somewhere…mega fuse? Some of these are earlier cars…. Though mention of a 400 amp mega fuse on there…

https://www.fullfatrr.com/forum/topic66876...ttery+fuse

https://www.fullfatrr.com/forum/topic29815...ttery+fuse

https://www.fullfatrr.com/forum/topic66509...ttery+fuse 2011 Range Rover Vogue SE 4.4 TDV8

Previous cars :
2003 Range Rover Vogue TD6
1999 Discovery Td5 ES
1995 BMW M5 3.8 6 speed
1992 Range Rover 3.9 Efi Vogue
1992 BMW M5 3.8
1988 BMW 735i SE
1989 Ford Sierra XR4x4 2.9i
1981 Ford Fiesta Supersport

Some people refer to the box next to the positive terminal as a collision related explosive disconnect device, others as a 400a mega fuse....

If you have a continuity tester, the first test should be to ensure that there's not a broken circuit inside that box.

https://www.fullfatrr.com/forum/topic41516.html?start=15

Thanks for the reply’s. I have checked the large fuse earlier on the red positive, it is in tact.
I’m going to continuity test all fuses tomorrow. So annoyed with myself. Such an easy job. Brown ground wire for some reason gave me a positive in my head, as brown is sometimes live in electrics!

Check all the fuses. Lots of ECUs and things have reverse polarity protection by means of a diode which will blow the fuse when powered up wrong way. MY11 4.4 TDV8 Vogue SE

I found it was the pyro fuse and a couple of others that may have been related. The only thing I can’t seem to get working is the electric mirrors, despite the common fix of pulling fuses 11 & 24. And the BCM fuse 27 I think. They were folding and working fine, now nothing I try gets them working. Any ideas?

No ideas, but thank your lucky stars that's all that's 👍