Car completely dead - Please help

[Mattcar]

Hi,

I was driving down the A2 in slight traffic, turned my heating fan to full and the next thing I know I have no power what so ever. Nothing, no lights, no hazzards, no sign of any life in the car at all.
To cut a long story short I was taken home on a flat bed pick up. (another chimaera owner passed and didn't stop to see if all is ok, I would have stopped)

Anyway,
I think it may be this 100 amp fuse I keep reading about. Has this ever happend to anyone else? I think something was overloaded when I turned the heater fan to full, because thats when everything instantly died.

Any advice would be greatly appreciated.

P.s Where do you get these 100 amp fuses from?

Matt

Edited by Mattcar on Saturday 13th October 22:20

Edited by Mattcar on Saturday 13th October 22:20

Edited by Mattcar on Saturday 13th October 22:22

[nix887]

Sorry to hear about your car! I can't help with what's caused the problem, but the 100 amp fuse is pretty cheap and I got my spare from a dealer. You can get a spare bulb and fuse pack, around £12 I think, and it has all the bits you might need.
Hope you find the problem!
nix

[GreenV8S]

That sounds rather like the main ignition switched feed has failed. It would be worth checking the connection between the ignition switch and the main loom, and also check the immobiliser wiring.

[Toma500]

Check your battery terminals are on ive had one come off before just when i parked up outside a mates house came out 2days later car as dead as a dodo called out green flag , they couldnt sort it trailered it to HHC they found the battery terminal off was not happy with green flag about that , still got a ride home from scotland in a nice big recovery lorry and a day off work

[Ozstyle]

I would check all the fuses in your fuse box as well.
I've recently mapped out the fuse panel layout and its nothing like the hand book. Its quite surprising how removal of certain fuses causes strange things to happen with the electrics. For example removing the heater system fuse on my car then turning the ignition on makes the cooling fans come on. However the remove the same fuse with the ignition on just disables the heater system. All very strange.

[shpub]

The bible has all the different fuse layouts that I know TVR used. That has about 10 or so variations and yes they often don't quite tie up with the handbook.

The 100 amp fuse that is normally referred to is the alternator one that protects the battery from an alternator short. If this fails the car's electrics are powered from the battery and eventually this will go flat but won't give a sudden loss of power.

There is a second 100 amp fuse that feeds the main fuse box and is located in the passenger footwell near the fuse box. May need a rummage to find it and bear in mind some early cars didn't have one.

I would guess that this is the culprit if the car is completely dead - no lights or anything although a quick check with a multimeter to confirm that voltage from the battery is getting to the fuse box is what's needed.

I do replacement strip fuses and the more resilient encapusulated versions if you need them. I also include them in the glow fuse packs that I do. www.tvrextras.co.uk and look in the fuses section.

[poorpeet]

Hanhing from the loom near the battery are twu relays & two blade fuses. One of the relays is the main relay the other is the fuel pump one. They are both the same so, as it's not likly that they have both failed I would swap them over. If every thing comes back bar the fuel pump you will know what the prob is. Check the fuses as well.

Pete

[Mattcar]

Hi,

Found the fault to be to be a blown 80amp strip fuse with a slightly melted casing. It comes of the positive terminal on the battery on a pair of brown wires about 6 inches long.

I'll order some new ones and see how I get on.

Just some quick questions:

Why has this fuse blown?
Could the heater fan on full power have over loaded the system?
I know it shouldn't have, but these cars seem to have thier own rules
(I had stereo and lights on as well).

Should it be 100 amp instead of the 80 amp?

Thanks for your replies.

Matt

[shpub]

The fuses can degrade with time and blow when stressed. The fact that the case is melted indicates that the fuse has got near its limit and when this happens it will get hot. This can cause the fuse to partially melt and thus reduce its current capacity. Switching the fan on was probably the last straw and it goes pop.

80A is a bit borderline. A 100 Amp would be a better choice as it gives a bit more margin and less likely to be marginal when all the electrics are on.

[spend]

Midi fuses seem much more substantial than strip fuses, the housing is also a little more robust - you can even insert strip fuses in the midi housing in an emergency. Well worth the couple of pounds extra if you are replacing them IMHO.

Dave

[BrianMillar]

I had cause to check that fuse on my car a while back and mine is an 80amp fuse down near the battery.
A 100 Amp will take more to blow it but the question is will the wiring take the extra power.
Fuses are there to protect the system without the correct size you could end up with a wiring loom fire.
Does anyone know what the original fuse was meant to be?

[spend]

They are normally connected via 2 cables each nominally rated at 50-70A IIRC. 100A fuse should be fine? Alt fuse I guess could be sized according to alt output - 65...100A (some have fitted 120A upgrades I believe), but I have only ever heard of 100A fuses assuming they are only to protect against short circuit rather than limit current since the alt is rated below their capacity. The battery to fusebox fuse (not sure what % of cars have these) should be rated on the cable limit to fuse box I would guess.

Dave

[Mattcar]

I've ordered some 80 and 100 amp fuses. I think I'll use an 80 amp and see how I get on. I would rather a fuse blow then a fire. I guess the original fuse may have degraded with time, but there still may be another reason why it blew.

P.s Lesson learnt. Keep replacement fuses and basic tools inside the car and not it the boot. When I broke down there was no way to open the boot so even if I had spares, I could'nt get to them.

Matt

[FlipFlopGriff]

Have you had a hot start kit fitted as this happened to me and it was a 20(or was it 25A) blade fuse near the battery (in the spaghetti area) - from memory its a fairly substantial orange cable. Replaced all fuses with flashing ones now so it's much easier to see what has gone and I seem to get through a few fuses, although it's getting less over time thankfully.
FFG

Edited by FlipFlopGriff on Tuesday 16th October 12:56

[Mattcar]

Hi,
Yes I have a hot start kit fitted.
Like the idea of those glowing fuses. Will look into that.

[shpub]

Mattcar said:

Hi,
Like the idea of those glowing fuses. Will look into that.

Hi Matt

They're on my website too: www.tvrextras.co.uk

[spend]

Circuit Breakers are nice

Dave

[Mattcar]

Got my new fuses. Fitted them, and all seems to be ok. Took her for a test drive (any excuse) and tried with lights,stereo and heater on. All seems to be fine.

Would recommend you all keep these spare fuses inside the car, as they are only a couple of pounds and take minutes to change. I learnt the hard way.

[Mattcar]

Got my new fuses. Fitted them, and all seems to be ok. Took her for a test drive (any excuse) and tried with lights,stereo and heater on. All seems to be fine.

Would recommend you all keep these spare fuses inside the car, as they are only a couple of pounds and take minutes to change. I learnt the hard way.

[gadgit]

I've just found the first 100 amp fuse, I think. its the one in the plastic holder right?
On top of the battery.

And the other one, I think I found it under the car near the starter motor, is that right.?? again in a plastic holder. and they should both be 100amp .