I checked my cossie today to see if the alternator is charging. Ive noticed when my lights are on in the dark the battery light comes on dim.

Anyway I checked the alternator for charging at the battery and it was.


so then I checked the voltage at the back of the alternator and it was.


So I wanna know where does the battery/alternator wire go to. Does it run across the bulk head then down the chassis leg to the alternator.

 

Also what gauge wire do I need to run a wire to the alternator from the battery.

 

On the 4i I just ran a extra cable to the battery from the alternator.

Steve

 

Yeah me too, used 10mm tri-rated

 

there is a lot of light that leaches into the other spaces on the back of the sierra instrument cluster, the abs light is the biggest culprit of this so make sure it's not just other lights int he back of the dash illuminating the battery spot

 

Na Dojj its defo the battery light. When I indicate it flickers with the indicators.

 

Did you not use a fuse. I googled about fitting a cable and some people on car forums were saying to use a fuse. Even though the original wire doesn't have a fuse.

 

Would this cable be ok. Im a bit shit when it comes to electrics.

http://www.ebay.co.uk/itm/TRI-RATED-...item3a7d86212e

 

No idea mate as I normally look to see what gauge it is or the mm2 number

 

The cable you have on the link will be ok.
Like you say on the these they don't have a fuse, I would not bother with one either.
What causes the battery light to glow : high resistance
This can be: loose/ bad connection on the feed wether it be corroded connection say onto the alternator or where it picks it's feed up, some pick up from the starter( I can't just remember on the cossies) if it does make sure it's clean/ tight, or if it's on to the batt check it there.
The easiest way to check, just try another temp main feed direct from pos on batt straight to the main feed on your alternator ( use a jump lead) then if the glow does go off you have got a bad connection/ dirty connection.
The chances are if yours picks up from the starter that's the most likely place it will be.
What you have is the big main feed to the starter from the battery, then on the same bolt you will have the feed to the alternator, take them off and clean them up.
If none of this works and all it can be then is the alternator itself.
Also I know yours is charging but it doesn't take much of a poor connection to make the batt glow ( high resistance ).
If you get no joy and can't get it to stop glowing I will tell you what you can do to make sure it's the alternator, but make sure you try the main feed to it first.
Hope this helps and you haven't lost the will to live reading all this... Craig

 

No

Steve

 

I ran another cable from altenator to battery too and it improved the voltage

 

Top info craig the sparky. Thats very helpful. Ive got another alternator just incase.

 

Where abouts did you route your new cable.

 

I routed mine along the bulkhead

Steve

 

I will have to give it a go. I was thinking about removing the wiring loom from the battery to the alternator and take that wire out and put a new one in.

 

My alternator is 90 amp. Will I need a 90 amp wire??

 

I had a similar prob on one of my other cars and after changing the charge controller the prob was solved. I can give you the genuine bosch number, if you need a bosch charge controller for 90A altenator. The bosch dealer will may have some.

You can change the carbon brushes of the charge controller, too, but sometimes it's the little board in the controller which is broken.

 

With the engine running and with the lights, heater and heated rear screen on, put one probe of your multimeter on the battery positive terminal and the other probe on the output terminal of the alternator and see what voltage you've got.

Anything under 0.3v I would say is ok but anything over would suggest you've got high resistance on that cable.

May as well check the earth side in the same way as well while you're at it.

if you've got high resistance, either clean up the connections or just make a new cable - job done!

 

You could to next size cable ( 16mm) which is rated at 110 amp, but the cable will be about 10 mm size on your car, and the alternator isn't ever going to run at full whack.
If they did there wouldn't be a car on the road with the correct size wire to alternator.
I would use what's in your link, buts it's up to you.

 

Im going to be doing this wire on mine very soon, just got an alternator wire from CW looms via Facebook .If it helps I will take some pics.

 

As said just run a new battery to alternator feed, if you follow the old cable back from the alternator then start to strip the loom tape back a few inches where it runs along the front chassis rail, you will find a solder joint where they stepped up the size of the cable, check this joint because mine hade corroded and worked loose which was causing the same problem you have.

 

Thanks for that matey.

 

How much did your wire cot if you dont mind me asking.

 

It looks like my alternator wire runs across the bulk head to me.

 

Mr Kitchen thanks for the info matey.

 

Had exact same prob this w/end It turned out to be shitty wire/connection on the positive side of the battery (one of the small wires)

 

It should go from the back of the alternator across to the loom which sits on top of the chassis' then it runs back and up behind the brake servo somewhere and then across the front of the bulkhead panel to the battery, that's how mine was routed from factory, its were its jointed where it joins the loom on top of the chassis leg that mine had gone crusty, I just cut mine at that point and at the battery end then run new.

 

Ive cleaned all the terminals on the battery.

 

TOSH thats where mine is routed too.

I checked for resistance in the wire and it seemed ok.

 

Not at all Glenn, Ł24 delivered . Terminals are neatly finished ready to fit.

 

Cw looms do them on eBay aswell!

 

I will have a look on ebay now.

 

Cant find them looms on ebay.

 

Last time i looked on ebay he did have one item (hairbrush kit) . I had brilliant service via FB with him and bank transfer. Will purchase the starter wire Friday if your not on FB Glenn just ask and I'll order for you no problem .

 

Thanks matey. Im not on fb but ive ordered some cable off ebay.

 

No prob mate .

 

It's a common problem, with the heat the cable builds resistance, not to mention the age factor!

There is nothing wrong with the power you have, even with a new cable I doubt the two will marry exactly, due to the resistance of the cable.

The cable runs directly, it is on ERST's it goes via the starter.

As said the problem with the light is caused by unequal power (it doesn't really tell you much to start with) basically your probably getting less power on the ignition live side of it than on the alternator side, hence it illuminates.

There is another problem where the power drops to the car side, it's worth checking the voltage at the ECU...

Martin

 

Is it best to run the old and new Alt wire together or just take out the old , Im thinking the latter?

 

You won't be able to as it runs in tape along with other wiring, the best thing you can do is run another cable.

Martin