Jump to content
Do Not Sell My Personal Information


Electrical Help!!


MondeoNeil
 Share

Recommended Posts

Hi everyone,

After some help please.

We replaced our altenator on our 2004 Ford Mondeo 2.0 TDCI, and yesterday we had another problem...

The battery light came on and the readings on the trip computer and mileage reading cahnged to dashes like this - - - -

I stopped the car and turned it off for a few mins. When I turned it back over there was a screech noise as it started up and the digital displays were OK and the battery light went off.

I then made it about another 800 meters and the battery light came back on. I decided to return home and stopped the engine again. Left it for 20 mins came back turned it over and again another screech when it turned over and the light went out.

I have left it over night, went to get in it this morning and it wouldn't unlock by the key fob. Got in put the key in the ignition and NOTHING, not one light, not anything. Not even interior light will come on it is completely DEAD!

I am a bit worried that this may be something more than an alternator issue as obviously something has either drained the battery completely overnight or there is a further issue.

Any ideas, or help greatly appreciated!!!

Link to comment
Share on other sites


i would check belt is tight enough. and depending how much charge was in the battery to start with i would either get battery tested or change it. i had a battery that was on 1 min then struggled the next even had dashes come up on display.changed battery all ok now

Link to comment
Share on other sites

You don't really say when you changed the alternator; is this new problem immediately (ie, you haven't even driven the car once, to get the battery charged after changing the alternator and before the new problem) after changing the alternator, or something else?

  • get the battery charged; this may not help, but, guessing about the timing of the problems, is the only way that you will know that the problem isn't (partly) caused by the battery starting with next to no charge
  • ensure that the alternator drive belt is tight and clean of, eg, oil and water - the screeching is caused by the belt slipping. Now this could be just as the engine starts (the alternator mechanical load will be at its maximum in this condition) or it could last longer, but, in any case, it sounds awful and can limit battery charging.
  • look at the battery voltage - something like 14 volts plus when charging and above 12 volts with the engine off and the electrical loads off would be about right

the battery could be knackered (it is likely that the failure of the alternator has put extra charge and discharge load on it), it could be flat (alternator...again) or it could be something else draining current; do you, by the way, know that your new alternator is 'good'?

Once those are done, you can start looking to see if anything is discharging the battery 'overnight'; the battery voltage will usually be down a little (tens of millivolts, rather than several volts) after an overnight rest, but, if the battery voltage is severely down after an overnight, you have to go looking for what has caused it - check, for example, that everything on the dash and in the interior does seem to go off once you have locked the car.

Link to comment
Share on other sites

Sorry the car has been used everyday since I changed the alternator in August 2013, and it was changed because the one that was on it was original and gave up. And the problem only started yesterday.

Link to comment
Share on other sites


Ah, ok. I'd got the impression that the alternator change might have been a bit more recent.

Anyway, do the belt, and get some voltages.

Link to comment
Share on other sites

Cheers BOF, belt ordered for tomorrow and an alternator too. How difficult is an alternator and belt change on your drive? Is it an easy job or does half the engine have to come out to get access to it?

Link to comment
Share on other sites

When I changed all the pulleys I took the alternator out (not to change it - just needed it out the way to get the tensioner off). I had to drop the engine about four inches, but watch the boot on the inner end of the tie rod as you'll knack it if you let the engine go too low.

The second time I had the alternator off to change the top idler, I didn't drop the engine and had to leave the alternator in the back of the engine bay as I couldn't get it out.

It's not a hard job either way - just be SUPER careful lowering the engine. I put the car on stands then the jack under the sump with about four pieces of thick plyboard between. Lift it just enough to let the jack take the weight, then undo and remove the O/S engine mount. CAREFULLY AND SLOWLY (I cannot stress this enough), let the engine down on the jack, watching the suspension/steering components against the frame at all times.

(disclaimer: there is the potential to cause serious damage. do this at your own risk - not mine).

Link to comment
Share on other sites

Is there no way of getting it out with out lowering the engine? That's not something I would want to start doing!

Link to comment
Share on other sites

Is there no way of getting it out with out lowering the engine? That's not something I would want to start doing!

Yes, most people/ mechanics do not lower the engine, it is opening a whole other "can of worms" with the potential for more to go wrong and stripped or sheared bolts (due to them being sieized) etc

You can get access by taking the offside wheel and plastic trim/ wing inner off - you need to get a special tool (or make one/ get one made) for un-tensioning the tensioner and the belt is very close to the side of the engine bay - so its a tricky job - you might be better off paying a pro or get someone who knows what they are doing to do the work

Because of the difficulty and/or cost of changing the belt, it is recommended that you change the belt, tensioner/ idler pulleys and crank pully all at the same time (so it should last a good few thousand miles and you are not having to do it again soon) - best to use Gates kits or genuine Ford - typical costs are £200-£250 but prices can change (used to be twice that)

Link to comment
Share on other sites

Cheers BOF, belt ordered for tomorrow and an alternator too. How difficult is an alternator and belt change on your drive? Is it an easy job or does half the engine have to come out to get access to it?

I don't know how we got from 'maybe the belt is greasy or loose' to 'I'm going to change both the alternator and belt' in one easy jump, without even checking the belt condition or tension. And, anyway, the tensioner could be the problem.

Link to comment
Share on other sites

Is there no way of getting it out with out lowering the engine? That's not something I would want to start doing!

It might be possible as FOCA said. But it depends how long you're willing to sit there, trying to jiggle a ruddy great alternator about to get it through a hole it does not really want to go through. Personally, I gave up after about five minutes. (and yes, I had the wheel arch liner out).

Having done it twice before I'd have no problem dropping the engine again. It's pretty daunting if you're a first-timer, though, but it does make the rest of the job a hell of a lot easier.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share




×
×
  • Create New...

Forums


News


Membership