1994 Fiesta - sudden dead battery - carled
After interrogating my dear wife for a few minutes.. this is what appears to be what happened.

Background info is that every now and then she notices a "squealing" noise from under the bonnet. also her battery light tends to come on very occasionally, but "only when driving through puddles..." (women....)

A few days back it was raining REALLY heavily and was pretty cold. She was driving the girls back from school and was in a slow moving traffic jam for ages with all the electrics (fan, front demister, rear demister, radio, lights, etc...) going. Suddenly the radio cut out, the dashboard lights all went out and the car engine seemed to labour a bit. She waited for a minute or so, then turned off the rear and front demisters and all the lights came back on and the radio did too.

She drove home (another 10 miles or so) then parked up normally. Next morning, she went to use the car and it was dead as a doornail. Not a flicker of light anywhere to be seen and no ignition possible. RAC called out, not really got much of a clue, measured battery at "2 volts" apparently, connected jump leads and got it started, then measured again and said it was receiving a very slight charge but not enough. He called their tech line who mentioned a "faulty fuse box" as a posisble problem. He followed us to the local garage where we dumped it until Monday so they could look at it. Garage called us back saying they weren't good enough with electrics to diagnose the problem, but they charged the battery overnight and my wife was able to start it this morning at the garage and drive home. By the time I got home a few hours later, it was all dead as a dodo again.

I connected my jump leads to it and started it up, then disconnected the jump leads. Immediately the main lights dimmed and the engine laboured a bit, but it kept going. Inside, no dashboard lights at all. Revving the engine caused a fan-belt (or alternator belt? Don't know?) squeal. Whilst sitting there I decided to turn on some other electrics and picked on the rear window demister... instant engine death - just like a kill switch and all lights off totally (including interior light - not a flicker of light in there) and ignition completely dead again.

This is all very familiar to when my old fiesta's alternator gave up years ago, but not entirely... I'm pretty sure that it got to the point where it completely tried to run off the battery and couldn't be driven, whereas my wife's appears to be fine until the engine stops and the battery doesn't appear to be holding its charge, even when it has been fully charged...

Anyone got any ideas on the problem based on this description please?
1994 Fiesta - sudden dead battery - yorkiebar
If the battery is only receiveing a slight charge, no doubt its without any elelctrical load, and discharching when it has electrical load then it will die as soon as there is too much load if the alternator cant cope with it.

Not a definite diagnosis but it does sound like a dead alternator.

What needs to be checked is whether its not charging or there is a fault in the system not letting the charge though etc.
1994 Fiesta - sudden dead battery - Dynamic Dave
I take it the alternator belt has since been tightened or replaced to eliminate the squealing? The squealing being that the belt is slipping on the alternator pulley and thus not charging the battery properly.

1994 Fiesta - sudden dead battery - carled
Well I'm not entirely sure it IS the alternator belt! It could be the fan belt, I suppose... We have our mobile mechanic coming out in a few days... just wanted to educate myself to have an idea of what it could be!
1994 Fiesta - sudden dead battery - Dynamic Dave
It could be the fan belt, I suppose...

Isn't the cooling fan electric on a 1994 Fiesta?
1994 Fiesta - sudden dead battery - jc2
Yes;belt drives w/pump & alternator.
1994 Fiesta - sudden dead battery - Simon
Well I'm very unimpressed with the service you received from the local garage. Charge up the battery and send them on the way is really wise. It certainly sounds like your alternator is goosed, why not take the car down to a decent auto electrician and let them sort the problem for you.
1994 Fiesta - sudden dead battery - Lud
Sounds as if water pump bearing or alternator bearing has partially seized.. Squealing is belt slippage. Take the belt off and spin both pulleys to see if alternator and water pump turn fairly easily. If so refit belt with proper tension. Otherwise replace defective unit. Easier said than done as usual.
1994 Fiesta - sudden dead battery - jc2
It's a simple job to change an alternator on a Fiesta of this age(unless you have A/C).
1994 Fiesta - sudden dead battery - RichardW
First, it sounds as if the battery is shot - it seems unable to hold a charge overnight, so I would replace that (not very expensive). Then I would tighten (at least, probably reaplace) the alternator belt. Once this is done you will be able to assess whether the alternator is charging properly (it will struggle if the battery is totally U/S and / or the belt is slipping).

Is it illogical? It must be Citroen....
1994 Fiesta - sudden dead battery - carled
Is it a case of buying the relevant Haynes manual and diving in then? I'm pretty diy-competent and used to enjoy dismantling my old mini years ago! Is replacing the alternator a nightmare job (Model is the 1.3 equipe - no a/c) or something I could achieve without too much trouble, do you think?

Anyone know how I'd go about finding out the correct alternator model I'd need? Is there an online resource anywhere that'll allow me to search based on car year, make & model?
1994 Fiesta - sudden dead battery - jc2
Go to your local car spares shop;most operate exchange systems-or even Halfords or a Ford dealer.
1994 Fiesta - sudden dead battery - Ruperts Trooper
For an alternator, try www.alternatormart.co.uk
1994 Fiesta - sudden dead battery - Claude
I wouldnt just replace the battery without testing it to see if its really a dud. If you've got alternator problems the battery might be okay. Rather than losing a charge overnight it might not have had any significant charge in the first place! (A 12v lead acid battery is effectively discharged even when reading 10.5volts). I would suggest charging it overnight out of the car and then test the SG of each cell. (You can buy a hydrometer from Halfords or most motor shops for about £3.)
1994 Fiesta - sudden dead battery - carled
1994 Fiesta - sudden dead battery - Screwloose

I'd be a bit cautious about changing any component until a competent person has thoroughly investigated the inconsistencies here. A dead battery shouldn't have had any effect whilst driving and an alternator charging fault, or slipping drive belt, wouldn't leave a battery standing at 2 volts, or for it to go flat after recharging. That indicates an internal short, or a very substantial drain on the battery and that could be an alternator diode issue - amongst others. [Is this a diesel? Is the alternator getting - or smelling - hot?]

The possibilty that there's a combination of two, or more, faults here can't be ruled out.
1994 Fiesta - sudden dead battery - carled
Update. Mobile mechanic finally came out on Tuesday. Tested battery and two cells are dead and not charging, so a new battery was needed anyway. He went and bought a new battery, fitted it and tested the alternator. Said it was old but working fine. However, dashboard lights still didn't come on inside car and, even though the car started ok, by the next morning having been left standing, the new battery was utterly drained too.

The mechanic said he didn't think he'd fixed the problem, but didn' thave enough time to do a thorough electrical test. He's a bit befuddled by it all now and hopefully we'll get more joy when he next comes back. Don't know how this fits in with any other theories on here at present?
1994 Fiesta - sudden dead battery - Micky
"> After interrogating my dear wife for a few minutes<"

You interrogate your wife??!! Each to their own ;-)

If a new battery is dead overnight then there is probably a leakage problem (!)

Disconnect battery, connect battery charger overnight. Measure and record battery voltage without connecting to car. Connect to car, measure and record battery voltage. Start car, allow car to idle for a few minutes. Measure and record battery voltage at idle. Measure and record battery voltage at 2500 rpm. This will determine if the charging circuit is OK.

Disconnect battery, leave overnight. Reconnect battery, does the car start readily? If so, the battery is OK .... probably.

Measure current flow from battery with no load. If possible, measure current flow from battery with alarm and immobiliser activated. If you have the time, remove various fuses to identify the device(s) that are causing current drain.

If the above doesn't provide the answer, buy a Toyota.
1994 Fiesta - sudden dead battery - Micky
Edit: a failing alternator can ruin a battery, and vicky verky.
1994 Fiesta - sudden dead battery - jc2
If the above doesn't provide the answer, buy a Toyota.

Which will do the same but cost you a lot more money to fix!!
1994 Fiesta - sudden dead battery - Galaxy
Sounds to me like you have something causing a permanent drain on the battery, even when the ignition is switched off. Could be an internal short in the horn, boot lamp not switching off when hatch is closed, or something more serious.

Your mechanic should have connected an ammeter in series with the battery to check for this. Did he do so? Might have used a clip-on ammeter instead, if he happened to be so equiped, which would also do the same job.

Something else occurs to me. There are about 3 separate cables which have to be connected to each of the battery terminals, a heavy think one and one or two smaller ones. Have you checked that all have been put back correctly?

I have to agree with your mechanic on one thing, though. I don't think he has fixed the problem either!

1994 Fiesta - sudden dead battery - ajsdoc
Agree, mechanic doesn't sound great. Why not go to an auto electrician, horses for courses and I think he may save you money with a proper diagnosis rather than just replacing bits, being unsure whether it's fixed, and then no doubt replacing something else to see if that works.
1994 Fiesta - sudden dead battery - Steptoe
Hopefully you are sorted now but if not suspect the alternator is discharging battery (faulty diode pack)

The alternator is permanently connected to the battery so the discharge will occur even with ignition off, it may well still be charging to some extent when engine is running. You might get some arcing when disconnecting/reconnecting positive terminal with everything switched off to prove this.

I assume that someone has already checked the engine/chassis earth lead?

One mans junk is another mans treasure
1994 Fiesta - sudden dead battery - Claude
A colleague of mine is having a similar problem on a 1992 1.4 Fiesta. Battery completley flat on a couple of occasions after leaving for a few days. No obvious reason for current drain, battery apparently in good condition and holding charge when disconnected. However on reconnecting another fully charged battery I noticed that the LED display on the radio was glowing but without any figures or letters showing and without the ignition being switched on. Disconnected the battery and the LED went out. Also discovered the radio doesnt work anyway whereas was working perfectly before. So removed fuse 2 (radio and interior light) and have not had any problems since.
There may be other faults but certainly the radio seemed to be drawing a current in some way which I havnt worked out. I have heard that, in certain situations, broadband wifi can have strange effects on car radios and certainly this car is normally parked in an area thats full of wifi signals so we'll bring it round to my place ar some point and take the radio out and see what we can find.

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