Charging problems

[Danboi2]

Hi guys ive got a problem with the car not charging properly, ive just had a brand new battery fitted and ive tested the battery with a voltmeter and with the car off and the reading was 12.5v and when the cars started on idle it drops to 12.2v .Ive had the alternator taken off and tested at a starter and alternator place and they said it was charging properly, and ive replaced the alternator with an old one that I was using before I replaced to an up rated one and the reading it still the same, ive also tested using a different battery, ive disconnected my amp wire from the battery incase it was this that was draining the power but still the same, the only things that have changed on the car in the last few weeks is the battery and replaced the starter motor. Any help much apreciated

[Os8472]

Disconnect the battery, jack the front of the car up and get the drivers side front wheel off and put an axle stand under there, get your torch and have a look at the back of the starter motor, there should be 3 wires going to it, a small white wire on its own and 2 bigger wires, 1 grey and 1 red, both should be connected to same terminal on the starter

Check that and report back

[Markey Mark (BD)]

Sounds like a problem with the wiring then mate.

The yellow wire going to the top of the alternator, has it got 12v when the engine is running? Also is it in the correct position, i:e not swapped places with the purple one next to it.

Also check the main power wire that comes from the postive terminal of the alternator and goes to the starter, see if there is no breaks in it and it has good connections each end.

Also check the earth lead for the alternator, i've had one where the earth lead broke

[Os8472]

The 2 wires at the top of the alt are in a plug that only goes in one way so unless someone has cut it off and used crimps they can't be the wrong way round.

[Markey Mark (BD)]

The 2 wires at the top of the alt are in a plug that only goes in one way so unless someone has cut it off and used crimps they can't be the wrong way round.

Not many out there left with the brown plug (from what i've seen recently) so worth checking if his has been cut too. But your right Olly, can only go one way if plug is on there.

[Os8472]

Not many out there left with the brown plug (from what i've seen recently) so worth checking if his has been cut too. But your right Olly, can only go one way if plug is on there.

True, I've cut the one off mine but that was because it had melted gotta love french electrics, the only other 1 I've seen with it with it cut off though was at FCS 08, I think it was a white 9 or 11, the guy couldn't understand why the battery wasn't holding the charge, 30secs with my hand in the bay and all was good again

[ranj]

I had this problem when i rebuilt the engine and put a new loom in .... turned out the wires in the brown plug were the wrong way round ! ..... check the colour of wires going into the plug from the drivers side and let us know which colour is left and right and then i will check mine for you

[Thundercat]

Yellow wire to top of alternator usually losses 12v due to engine plug corroded at inner wing, renault used to mod loom by running a fresh wire to ignition switch. This also gave better charging to battery. Bought many a 5 with this mod carried out and reliable fix.

[Danboi2]

Sorry for the crap pics

[Markey Mark (BD)]

Sorry for the crap pics

That looks right mate As in the brown plug at the top

[Danboi2]

whats the purple one for becuase that nearly snapped when i was taking the picture but the yellow one seems fine

[Markey Mark (BD)]

whats the purple one for becuase that nearly snapped when i was taking the picture but the yellow one seems fine

Purple one is for the dash light

[Danboi2]

isit worth trying to clean that block or cut it off and fit crimps on the end

[Markey Mark (BD)]

Check if you got 12v there first, if you have and the connection is good then its ok to leave it

[Danboi2]

how do i test that?

[Markey Mark (BD)]

Using a multimeter mate, with engine running/ignition on see if you have 12v there

[Danboi2]

I think thats the problem mate its reading was only on 4v on the yellow wire but on the red power wire on the alternater it was on about 14v

[Os8472]

Where are you putting the test leads? one on a good earth or to the negative terminal on the alt? and the other on the yellow wire?

[Danboi2]

i first done it neg on the alternator and to the yellow wire and then just to be sure from the battery negative and to the yellow wire

[Os8472]

That sounds ok, when you said you were only getting 12.2v at idle, where were you taking that reading?

If the alt is putting out 14v on the red/positive wire then there is a brake in the circuit to the battery, disconnect the battery and the alt and do a continuity test between the positive at the and at the alt, should be a direct link

[Danboi2]

was taking a reading at the battery, will give it another check tommorow when i got some proper light

[Os8472]

The fact that the alt is putting out 14v but the battery has only 12.2v means its not getting the charge from the alt, which basically means the two are no longer linked.

The continuity test is very simple, first off what type of tester are you using?

[Danboi2]

its a basic one like this

[Shane P]

its a basic one like this

Sounds like you nailed the problem in post 17 bud, run a fresh wire and see how you go

[Os8472]

Right then, put the black lead in the black port on the bottom marked with CON and the red lead into the next port up, next disconnect the battery and the alt, put a piece of cardboard or something underneth both terminals to insulate them from any other metal.

Get your tester and put it on the 200ohm scale then put the leads together and note down the reading that comes up, dunno if your tester bleeps or not, next put one lead on the end of the wire from the battery positive and the other on the lead from the alt poisitive and see what reading you get, should be the same as the reading you got before.

[Danboi2]

ok thanks alot mate much appreciated will have a look tomorrow

[Os8472]

No probs but my bet is still the connections on the starter

[Danboi2]

right ive just done the continuity test and across the voltmetre its 0.5 and from the battery possitive to alternator possitive it was also 0.5

[stu21t]

dodgy earth?

get some jump leads
connect 1 from them on the - battery post and the other end on the casing of the alternator and test again at the battery with the engine running,
if it goes up it means you have a dodgy earth somewhere

do the same on the + side and will show if you have a live feed problem.