still on an old topic about chargel

[slickster]

My charge light came on when my small wire broke off to the positive side of the battery.  I put it back on and the light does not go out.  The battery is charging thou.  There is two lights one light stays on all the time the other light goes out when the rpms get up to 2000 to 3000.  I changed the diode board to the thunderchild.  The red glare continues It is real bad at night any ideas?

[Bob_Roller]

You need to know which light is doing what .

The two red lights one is 'GEN' thats for the alternator, the other is 'OIL'  for engine oil pressure .

Which light stays on all the time ?

[Barry]

There are 4 warnings lights arranged in a square. The 2 top red ones are "Generator" on the left and "Oil pressure" on the right.

Which light stays on and which goes out at 2000 to 3000 RPM

[Bob_Roller]

If it's the oil presuure light, I wouldn't run the engine until you find the cause .

Not too uncommon to have the insulation on the wire that goes to the low oil pressure switch to get brittle and break off .

If the bare wire touches the engine, it completes the circuit to turn the light on, regardless what the switch is doing .

[nhmaf]

If it is the oil light that oil pressure switch is just back and below the left side cylinder , sticking out of the engine case like a sparkplug - they can also crack (usually leak then) or the tab can break off.  

When was the last time you changed/checked your oil and oil filter?

[slickster]

Come on guys I know which light is the charge light after 25 years with this steed.  The light does two things tells you if it is and when charging and wait for if you have bad ground.  You know this.

[Bob_Roller]

Not really being familiar with you, we assume that you are new to airhead BMW's, the charge light has been confused with the oil pressure light more times than you can imagine .

A quick test for the voltage regulator is removing the regulator frm it's connector, place a jumper wire between the blue and black wire .

The light should go out above around 2000 rpm's if the regulator was faulty .

According to Rick Jones airhead charging book, if the regulator isn't the fault, the rotor, stator, diode board ( you removed that from the list with your replacement) and wiring .

[montmil]

Come on guys I know which light is the charge light after 25 years with this steed.  The light does two things tells you if it is and when charging and wait for if you have bad ground.  You know this.

Actually, the alternator warning "idiot light" does more than you suspect.

Paul W. Burch wrote the Tech Tips column in the BMW Owner News magazine for many years. He wrote an excellent essay in the February 1996 issue on six (6) problems that can be diagnosed by the amount of light emitting from the alternator warning lamp. Quoting Paul, "You can learn a lot from an idiot."

With the OEM charging system, an alternator warning light that remains brightly lit indicates either: 1) an open field current diode, or; 2) a shorted negative diode.

You state that you had recently installed the Thunderchild diode board and then the problem occurred with the lamp. If all else within the charging system remains unaltered, a review of the T'child installation and its wiring, or a contact with the vendor, may provide an answer.

There's an old saw about resolving operational issues that advises revisiting the last change made. Quite often, that's the source of the problem.

Good luck.   Monte

[Bob_Roller]

Monte, go back and read the first entry in this thread, the small red wire broke at the battery, I'm sure the wire was repaired, the light came on then, replaced the diode board and the light continues to stay on .

Just based on what was written, I'd say the diode board isn't the problem, if the problem existed before and after replacing the diode board .

Now if I get 'flamed' for this so be it .

You have two red lights one for low oil pressure and one for charging system .

One light goes out at between 2-3000 rpm and one light stays on all the time .

If the light that goes out at 2-3000, most likely it is the charge light, a bit later than it should, this would explain why the battery isn't low on charge and the diode board didn't help the issue .

If the oil pressure light is on until 2-3000 rpm, you have a very low oil pressure problem, if the oil pressure light stays on all the time and the engine is still running, most likely it's a faulty oil pressure switch or grounded wire somewhere in the circuit .

Let the bullets fly !!!!!     [smiley=rifle.gif] [smiley=rifle.gif] [smiley=rifle.gif] [smiley=shoot.gif] [smiley=shoot.gif] [smiley=shoot.gif] [smiley=shoot.gif]

[tvrla]

Come on guys I know which light is the charge light after 25 years with this steed.  The light does two things tells you if it is and when charging and wait for if you have bad ground.  You know this.

Reminds me of a mid-west joke from my youth: car rear-ends old PU middle of nowhere. Car driver, boiling mad, asks PU driver why the hell he was stopping suddenly? PU Driver says "Everybody knows I turn here!"

slickster - your original post sure didn't sound like someone who knew his beans - two red lights were mentioned and how one stayed on and the other went off at 2K. Cmon dude - after owning the bike 25 years you should know when explaining a problem for the mechanic, all the relevent data with specific items are important to resolving the issue. So we have to guess at which two red lights those are, why someone wouldn't specifically say "the charge light goes out at 2K, or the oil pressure goes out at 2K...and so we figure it's gotta be a newby.

I'd also suggest proof-reading your postings for accuracy, typos and that they communicate exactly your viewpoint.  

[montmil]

... the small red wire broke at the battery, I'm sure the wire was repaired, the light came on then, replaced the diode board and the light continues to stay on.

Oh, that little red wire. A VOM would be helpful to trace the "little red wire." May have another break further downstream.

I recently had a vehicle that brought up a "check engine" warning light right after I rolled over a speed bump... not fast, mind you, but rolling. Turned out to be a wire broken inside a perfectly normal looking sheath. Not pinched. No visible damage. Took awhile to find it but that's all it was.

Garage fairies someone here abouts recently called 'em.

[Bob_Roller]

The red wire attached to the postive terminal of the battery, supplies electrical power to all of the circuits of the bike, if it's broken, nothing  electrical on the bike will work .

[montmil]

OK, the jumper wire will verify regulator ops. That's an easy check.

The smaller 2.5mm / 10 gauge red wire coming off the positive battery terminal on both my '81 and '83 R65s goes to a connector block somewhere under the fuel tank.

From there, multiple wires branch from the connector plug to, IIRC, the ignition switch, special equipment connector, starter relay and headlight relay. Maybe more.

Loose connections, corrosion or broken wire/s may be hiding. Where's Columbo when we need him?

Monte