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battery warning light stay on


Tibout

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hi there

just finish my conversion today and start first time :) i took off my old TD and put it a defender 200tdi engine. such a difference! the only issue i'm having is my battery light stay on and the alternator is working as normal does'nt seem to loss any power. The thing is that i did'nt have the wiring plug on my bulkhead to plug the wiring from the engine on as it should be normally as some cowboys had cut it and repalce it with these white connectors so i had to figure out which wire connect to each other. where will the alternator warning light wire be connected normally. if anyone could help i'll really appreciate.

thanks

thierry

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On my loom, its an old 86 n/a one (hooked up to a 200tdi) coming from the alternator there are 3 wires, 2 are brown fat ones taking the current from the alternator, the other is a smaller brown wire with yellow trace, I belive this is the indicator wire to say that the alternator is working, I've not actually delved into the charge system as of yet.

What wires have you connected to the alternator? and where are the wires you don't know what to do with? Do you have info on colours etc...

Take some pictures and post them up.

Mav

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Found this sort of explanation, but it goes with what I was thinking: there is like a voltage balance in the back of altenator (NOTE: its off a VW website "Necessity for the Alternator Warning Light" The Basic landrover circuit cannot be far off this.

The system is very simple, but it's absolutely critical that you get it right. The (D+) terminal on the alternator MUST connect to a functioning warning light in the instrument cluster. There should be just one wire (blue) from the (D+) connector on the alternator to the button on the bottom of the normal indicator light in the dash. The dash light is also wired from the (D+) (Blue) to ignition terminal #15 on the coil, which in turn is connected to the positive (+) post on the battery (Black). There is no ground wire on the light; the body of the bulb is connected to ground via the light holder (which also provides the ground connection for the other dash lights as well.) The three bulbs (ALT/OIL/TURN) all have a common connection in the socket which goes to ignition terminal #15 on the coil (which receives power from the (+) post on the battery by way of the ignition switch).

The alternator must get a feedback current through the "Alt" lamp in the instrument cluster so it can sense the battery voltage; it uses that as part of the alternator's internal circuitry needed to charge the battery. In other words, with the ignition on but engine off, the indicator light sees 12 volts from the battery (via ignition terminal #15 on the coil) and glows, but with the engine running, it sees 2 volts (14 volts minus 12 volts) running the other way, from the alternator. It doesn't glow (needing more than 2 volts to do that), but the alternator still "sees" the connection to the battery.

So -- If the Alternator is charging, the (D+) terminal has 12 volts on it; the blue wire from (D+) carries 14 volts to the "Alt" light in the instrument cluster. When the engine is running, there is 12 volts on the *other* side of the lamp from ignition terminal #15, so potential difference is only 2 volts and the bulb doesn't light. But, if the alternator dies or the drive belt breaks, there is no voltage on (D+) (looks like ground) and current flows from #15 thru the lamp to (D+), and the "Alt" lamp comes on to warn the driver of a problem.

My link

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Thanks for the reply lads I'm at work now so I'll take a picture this afternoon. As far as I know there's 2 brown one's from the alternator which I've connected to 2 brown one's coming from the bulkhead does it matter which connect to each other as on my old TD the 2 brown wire from the alternator are connected together then each one is connected to the 2 other brown from the bulkhead if that make any sense? Here are the small wires 1 brown with yellow, 1 white, 1 white with brown, 1 green. That's from the alternator. Maybe when I take a pic tonight that might more sense!

Thanks

thierry

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Thick brown one is main battery +ve (goes to the B+ terminal on alternator)

Brown with yellow strip battery warning light (goes to the D+, 61, L or N terminal, on alternantor - depends on your alternator)

White wire is fuel stop solanoid (on rear side of the injector pump)

White with brown stripe is oil pressure warning sensor (in front of oil filter)

Blue with green stripe is themostat temp sender wire (front of engine above/aft of the water pump

The thick brown ones all go to the same place so don't worry.

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warning light wire is brown/yellow trace at alternator end it connects to WL or IND, then runs to dash [same colour code] to the warbing light, if it's staying on when engine revved, alt has a rectifier or diode pack fault.

Can you get spare voltage regulators for Alternators? or once they go is that it? - new alternator

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HI just change my alternator this morning put a new one from paddock i'm pretty sure i've connected the wire from the alternator properly small brown and yellow to D and the thick brown one to N and then i think igoes into a loom to the starter motor not sure as its in a protective black sleeve :blink: then there's 2 brown and the small brown with yellow comes back and connected to 2 fat brown from the bulkhead and the brown yellow to another brown yellow fro the bulkhead. what could be wrong if the alternator is new and working what other connection could be wrong like an earth or anything :(

thierry

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Check the continuity of the wires. I recently replaced my engine loom as a lot of the wires were perished/cracked. Start with the engine part (small brown with yellow trace) then test it going through the bulkhead to the dash from the engine plug.

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Thanks for the reply I never thought of the continuity I've used the old connector which was there it might be faulty! Do I need to check the one on the 2 fat brown one's? I assume that's these ones bringing current to the battery? All the other guage works fine. Does these brown wire go to the dash behind and then to the fuse box? Because I've remove the tunnel when doing my conversion! I might have move something!

Thierry

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Also i know the 2 fat brown wire goes onto the starter motor as well as the small brown/yellow one. Just wondering if the starter motor was not earth properly would would that not charge my battery?

The brown and yellow wire does not go to the Starter motor, there is howeever a White with red trace that goes to the starter, combined with 2 large brown wires.

The earth for the starter should be a black wire that goes from the solanoid to the starter, then another strap from the motor to the engine.

Best thing to do it go round and test all your wires, the 2 brown ones are actually all wired together.

I'd say you need to test your Brown and yellow wireing, all of it, see if there is a break in it somewhere...

Also just thinking, what you can do it turn the engine on and see what voltage you're getting out of the Brown/yellow wire at verious points. firstly measure the output on the alternator, then work your way up to the bulb and see what you get.

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Hi I think my issue is with an earth! On the solenoid there's 2 medium brown wire connected to the positive from the battery and there's the white and red plug in( not brown yellow sorry). Then there's a big brown wire which is connected to a cable from the chassis. Which then goes to the negative on the battery. But there' no connection from the starter motor to the engine block ! Could that be where I got it wrong?

Thanks for the help

thierry

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Hmm, I doubt that's the problem as if your starter motor was not earthed it wouldn't work, it's obviously ok as you can start the vehicle, I guess on mine its a "back" up so the motor properly earths.

Not having this souldn't give you your problem...

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200tdi should have a earth strap from the PAS pump/Alternator mounting bracket [long bolt head facing to rear] the other end connects to a bolt/nut at rear face of left hand chassis part of engine mount & the normal earth from battery neg terminal to gearbox/transferbox joint bolt.

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I've used my old power steering pump and alternanor is new there's no earth cable conected to either of them and my engine itself is not earth. I was wondering maybe the alternator is not earth so that is can make a close circuit. If that makes sense! I'll try to do a continuity test tonight. So the two fat brown wire shoud run from the alternator to the bulkhead and where after? What about the one's from the starter motor the 2 medium brown and the big brown ones I assume one goes to positive and negative( earth) of the battery?

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don't connect any brown wires to battery negative terminal, put all on the positive termnal.

bolt item 13 on this TD PAS Pump/Alternator bracket parts diagram, should have one end of the engine earth lead under the head/washer. other end fits as described above.

same bracket as on Defender spec 200tdi engines.

post-20-049468800 1286552417_thumb.jpg

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So what's that other thick brown wire connected on the starter motor? Should it be with the other 2 medium brown wire as well? And then the black strap from the chassis connect to the other connection onto the starter motor?! Because I've put that big brown one to the strap which then connect to the chassis. Will this be what I got wrong?

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