Electrical Fault - flat battery... smell of burning

[r055]

it started a good few months back when i went to start car and i get the dreaded clicking noise.

so bought a new battery - seemed ok.

few weeks later, i get into car to drive it and the electrical/ plastic burning smell was really overpowering. then the battery light starts flickering slightly on overrun - if you accelerated it would distinguish it. Then eventually it broke down - AA out and new alternator fitted through parts and labour. burning Smell away and battery light no longer there.

Sat morning, took two attempts to start it (usually first time with no hesitation even if been sitting for a few weeks) once started and run for a few miles on way to rendezvous point in EK, the smell started to come back. Then on the run I noticed the wipers going marginally slower than normal, but thought it was my imagination.

We stopped at side of road waiting to hear from Bertie who had broken down behind us and i switched my engine off. Went to restart and it and the clicking appeared again.

Nizzy and Gizmo gave me a bump start and off we go again. Smell getting worse.

on sat night, woody attempts to break into car and the alarm goes off - but doesnt really as its more of a high pitch clicking and beeping.
in the morning - battery completely flat and no ignition lights

AA come out and start it first time using the jump lead module thingy.
He tests the earths, alternator and battery... alternator fine - sending charge to battery (14V?)
tries a battery tester - it reads 220ish (i think) but he says it should be up about 350 ish.
So he thinks its the battery thats goosed.

managed to get to M74 on way home and then the refill is screaming at me to fill up (been sh1tting myself to do this incase it doesnt start again) - started first time though.

Then when pulling out, the battery light goes on and stays on all the way home.


in the past few weeks ive noticed that Ive had the squeeky belt syndrome when the car is cold.

any ideas/ suggestions? Do i just take battery back for replacement under 12months warranty?
or should i be testing more things?

[cstrachan]

Buy a VX

Did you / AA check the battery was full?

If you are smelling burning it suggests a short someplace did you try using your nose to locate the smell? I am guessing you would get the battery replaced no probs as its new it would remove it from possibilties anyway.

[David]

This is only a guess but it sounds familiar to a fault I had some years back on a Peugeot . It turned out to be a wiring fault in the ‘voltage sensor’ wire for alternator. I'm a Caterham man, so I not sure if it's the same on the Elise but it used a voltage sensor wire to overcome voltage drop in the thick cable between the alternator and battery. The fault resulted in the erratic charging of the battery and overheating of the alternator. Eventually both the alternator battery failed and it all took a long time to sort out. I would check to see how hot the alternator gets, but if your battery light is now on it may be passed that stage - a look at the slip rings may well show they are burnt/damaged or the diode pack may have failed.

[robin]

Regulator will be goosed.

You need to check the wiring loom around the back of the alternator - you've been through both batteries and alternators ; simply replacing either of these parts won't cure the fault - the problem will be around the back of the alternator OR a vibration problem, but seeing as you've got a non-tuned standard engine, I don't think vibration is likely to be the problem.

Also you need to make sure that all the heatshields that should protect the alternator, etc., are fitted ...

Cheers,
Robin

[r055]

thanks Guys, sorry for delayed response - hopefully get a look at this at the weekend (weather permitting)