Battery Or Alternator?....

[sjw211]

I have a 2000 model year Focus 1.8 diesel.

I fitted a new battery about 6 months ago. It was in the winter and had slowly been getting slower on turnover in the winter. It was also still on the original battery so was confident it was dead...

The car isn't used a lot and I was maybe thinking it was a touch slower starting when I drove it about a week ago. Anyway the wife came to start it this morning but it wouldn't start. She said it turned over slowly. I came home and it just about turned over - but nowhere near starting.

I connected jump leads to another car and it started straight away - no problem. Took it out on the motorway and as I was coming off it, most of the dash lights came on and the rev counter ans speedo and mileometer went blank. I thought it had all cut out but when I pushed the clutch in and revved it was fine. Phew!! Drove the rest of the way home and the speedo, rev counter and mileometer came back on but the other lights occasionally went on and off - generally on.

Made it home OK and switched off and tried to start again - almost nothing. Clicking from around the dash and lights on and off but not even turning over.

Is sounds more like the alternator to me than a dodgy battery (a Bosch) but wanted some second opinions... :)

Thanks all.

Steve

[btmaldon]

I would check the battery terminals and remove, clean and refit all earth straps before going along the alternator route. Hopefully its simple.

[sjw211]

Thanks - will check for any obviously loose leads - but didn't notice any when 'jumping' it.

So I could get these symptoms with a bad earth then?

EDIT: Just looked and all leads on battery are nice and tight. They soon disappear into the depths though so can't tell anything from thereon..

[stef123]

Do you have access to a multimeter? ideally you need to know what the voltage is with the engine running.

[sjw211]

Do you have access to a multimeter? ideally you need to know what the voltage is with the engine running.

I may be able to get a hold of one. So I need to jump it again and put the meter across the terminals then?

[alz]

I agree with stef123 use a meter, with the car running the meter should read around 14 volts (13.5 to 14.4) if it is than this you will need a new alternator, also when you changed the battery, was it the right type

[sjw211]

I agree with stef123 use a meter, with the car running the meter should read around 14 volts (13.5 to 14.4) if it is than this you will need a new alternator, also when you changed the battery, was it the right type

Will try and get hold of a meter. It is the right battery - can't quite remember but know it's a high Ah one. Thanks all though. :)

[stef123]

Will try and get hold of a meter. It is the right battery - can't quite remember but know it's a high Ah one. Thanks all though. :)

The battery should be a lead calcium, not the standard lead acid as they dont work correctly with the ford smart charge system.

With the engine running, as said you should see around 14.4v at least (i believe smart charge can go up to about 18v - hence the need for a lead calcium), switching on the heated screen or something that requires alot of power will cause the voltage to drop momentarily but it should increase again.

[jeebowhite]

Dont jump straight into replacing the alternator - johnH had similar issues, and we advised him it was likely to be the alternator - he had it replaced only to find it didnt resolve the issue. In fact the issue was a snapped cable within a wheel arch - took a while to diagnose but got there in the end - thread is:

[sjw211]

The battery is a Bosch Silver 5 star 61Ah. Got it from Costco so will take it back there in the first instance I think.?.. Assume that is Calcium though?

Other than the lights and instrument failure (and failing to re-start), the car was running fine. With a fairly flat battery would you still expect that - albeit a diesel? Am hoping to get a hold of a meter today.

Is there a specific earth point I should look for and check/clean/tighten?

[johnH]

as jee has said i had a battery/alternator/smart charge issue.

heres a few questions.

do you have a battery warning light on your dash?

is there any DTC codes logged by using the dash technique? (it may log codes for everytime you jump the car as its not recommended)

do you notice the headlights dimming when driving?

if fitted does the heated windscreen activate when the engine is running?

you didnt really need a multimeter to begin with, following the dash technique it will tell you what voltage your battery is at, even when the engine is both on and off. off you should be getting around 12-12.5v with everything off (i mean everything like blowers, lights, radio) with engine started about 14.6v iirc.

from the symptoms you are describing it does point towards the alternator not charging the battery. the dials dying off mid drive could be down to an alternator surge and the circuit protecting itself as i have read that rev guages take their data from the alternator and drive belt.

if it turns out to be your alternator i have a denso 105amp from mine, still works (can tell from that link jee posted) will let it go for cheap if interested.

[sjw211]

Thanks all again.

johnH - read your thread and glad you got it sorted.. Can't believe you didn't look in the wheelarch first though.. ;)

Will try this 'dash trick' when I get home and post the findings.

Yes, the battery warning light was on - but so were all of the others. :huh

Didn't use the lights because it was light and didn't try them again once the engine failed to re-start.

[johnH]

thanks, aii this was a first for me and from other threads they were saying it definately splits near the alternator...how wrong they were. that and the fact im not confident mechanic so taking body parts etc is a no for me give me electronics and ill strip that mother down :P

let me know of the results and ill have a think.

[sjw211]

OK, am doing it now (laptop in car :) ).

After what I think is the engine speed one (I get 3 readings of 000.0 (mph,kmh and rpm) I get 03f.o (fuel?), 0000(?), 021.t, F119, L102, 086.F, 015.C, 027.C, b09.2 and then onto Ab-H which is, I assume, the ABS test. So it's the battery one that is b09.2? That is without the engine running. I have got hold of a meter (simple 5 light thing) and with it across the terminals it says the battery is low (2 lights). But that would be expected wouldn't it if it wasn't getting charged/discharging quickly? Also getting a DTC code of 9318 - battery low.

I'll move the other car into position and jumpstart it...

Anything specifically I should do - other than the dash test to try to eliminate anything..

EDIT: started it and tried the meter again and all lights come on - indicating a fine alternator.?.

The dash test now gives a figure for battery of b12.3. If I rev the engine this goes up to 12.8. Turning on the lights and heated windows and a/c drops it to around 11.1 - but revving increases it to about 11.2/3.

However, after switching everything off again it only went to 11.9 (not the initial 12.3) and revving only increased it to 12.2.

Hope that helps....

Sounding like alternator?

[stef123]

voltage is quite low for the engine running... should be atleast 14v..

my money is on the alternator mate :(

[sjw211]

I agree - it's just that the 'meter' with the lights lit up the top light which showed 14V. Probably need a proper meter to confirm.

[johnH]

reading those figures, rang similar to mine.

im kinda confused by this, i mean i think it could be one thing but it cant because of another thing.

it could be just as simple as a dodgy battery and the rest is fine. i mean dodgy like its not holding charge to get the car started again. but that could be down to a faulty alternator not charging the battery. being a bosche battery can you take advantage of their 5 year lifetime warranty?

if it was the alternator i would of said your car would of died altogether after around 30 miles. no power at all.

if it was smart charge your car would still start fine as the battery would charge and your alternator would be still good as it would be running in conventional mode.

try swapping your battery out of the good car but only if they match in power and if you have a method of charging it if it doesnt work. that way it will definately point you in the right direction.

[jeebowhite]

I agree with John, at this rate your going to have to use process of elimination to get this one hunted down. With any luck it will be damned obvious at the end of it! if you can, stick your head under the bonnet, make sure the alternator is earthing and their isnt too much rust around where it would earth, also make sure that the battery terminals are lubed up, if they are white and powdery, buy a tube of copper grease, and lube them up!

[sjw211]

Don't really fancy swapping batteries - don't fancy the hassle that often comes with it. I will take it back on Friday and hopefully swap it.

The battery attachments seem fine. Anybody know where any earthing points are? There's so little space nowadays. I'm not even sure where the alternator is lol. Assume on the left towards the back (looking backwards)? Is there an alternator earth and a battery one?

[stef123]

Don't really fancy swapping batteries - don't fancy the hassle that often comes with it. I will take it back on Friday and hopefully swap it.

The battery attachments seem fine. Anybody know where any earthing points are? There's so little space nowadays. I'm not even sure where the alternator is lol. Assume on the left towards the back (looking backwards)? Is there an alternator earth and a battery one?

the body of the alternator will earth to the engine, there will be an earth from the engine to the body somewhere..

I still suspect the alternator but alot of places will load test your battery for free