in my cabby is starting to bug me when using my leccy windows or sumtimes when braking it comes on ive had the car bout 4 months and its been doing all the time but the battery is charging fine. any ideas???

 

the motors could be pulling too much power off the batt cos they're knackered...

 

sounds like a bad earth

 

my old series 1 use to do it mate, and it got brighter as i braked aswell dont worry about it

 

Take the bulb out

 

the earth cable from the alt to batt is so small on the mk 4 , ive changed mine and all the earth straps , other than that id say alt is weak, or battery is old and tired , it certainly shouldnt be doing it though , get your batt checked 1st

 

How do "PROPERLY" (lol) test a batery??????

 

Never thought i'd hear u say that



My guess.........your brushes are going on your alternator.....and when you use high power items on the car the alternator can't keep up and stops charging momentarily. The battery light derives its earth from the alternator, and can only be earth when not charging..........

 

Thats an easy one, u get two wires from each terminal, stick your tongue out, and i think the rest is fairly self-explanitory

 

chances are the ignition feed to the battery light is sh*t. If the light only comes on dim this is the prob, fixed loads like that. Just run a new ignition feed to the bulb !!!!!!!!!!!!!!!!!!!!!!!!!!

 

If the alternator is charging there is no earth for the bulb so there isn't really anyway it can illuminate?

 

If the igntion feed has a low voltage, and the alternator is charging and sending a good feed 12v upto 14.4 then the resistance from the ignition feed can cause the bulb to "glow" dim. Caused when ignition circuits from the same supply draw current and the feed to the bulb drops to a lower voltage. Up the ign supply and it'll fix the prob for sure, I have done this on several escorts and it has worked every time. I just soldered a feed from the ign on the barrell (heavy black wire) and ran it to the ignition feed at the back of the intruments multi plug (black wire again i beleive) !!!

 

Ah yeah i get you, that would have to be a fairly high resistance though???? That car in my siggy did that come to think of it, driving at night u could barely see it glowing only when you were somewhere very dark.

Just out of interest, obviously you have the cure for that fault, but what causes the fault? That would have to be wiring breaking down or something?

BUT anyway.....do u think this could be the cause of the light coming on.....? I wouldnt of thought so myself?