Removed the alternator warning light and now it's overchargi

Need help on paint, paint prep, welding, engines etc?

Moderator: Moderators

Post Reply
smh00n
Mustang Star
Mustang Star
Posts: 312
Joined: Fri Jan 23, 2015 2:03 pm
Location: Sydney Hills District

Removed the alternator warning light and now it's overchargi

Post by smh00n »

The previous owner installed a massive alternator warning light which I removed today. Now the alternator is overcharging - 16-18 volts.

It's a Bosch 70 amp alternator which has a S and L terminal. I've run the S terminal direct to the battery with a new wire.

As an aside, if I plug the L terminal into the existing ignition-switched wire in the wiring harness both Sniper and MSD boot up and cause issues like run on.

Can't remember where I took power from for the sniper but would this affect the alternator?

Any clues based on this pisspoor description? I've trolled the interweb and nothing mentions having to run the alternator warning light. The S terminal seems to be used on this alternator to determine the battery voltage.

It worked before I started playing.....
unilec5544
Mustang Star
Mustang Star
Posts: 537
Joined: Thu Dec 16, 2010 11:04 pm

Re: Removed the alternator warning light and now it's overchargi

Post by unilec5544 »

So the 'S' terminal you can just connect to the alternator to battery feed at the alternator, no need to run a new wire to the battery. The 'L' terminal needs a 2 watt feed for correct excitation, but no more than 2 watts. Do you know the wattage of the globe you removed?
hybrid
Mustang King
Mustang King
Posts: 9352
Joined: Tue Jul 27, 2010 2:13 pm
Contact:

Re: Removed the alternator warning light and now it's overch

Post by hybrid »

You can't just ditch the light. Put one back in circuit and just hide it if you don't want to see it. Normally they don't charge at all without the light.
smh00n
Mustang Star
Mustang Star
Posts: 312
Joined: Fri Jan 23, 2015 2:03 pm
Location: Sydney Hills District

Re: Removed the alternator warning light and now it's overchargi

Post by smh00n »

right.....

I did buy a nice small LED as an idiot light. It's a Narva one but no deets on it.

I'll chuck it on and see what happens
hybrid
Mustang King
Mustang King
Posts: 9352
Joined: Tue Jul 27, 2010 2:13 pm
Contact:

Re: Removed the alternator warning light and now it's overchargi

Post by hybrid »

LED won't work. It needs the filament of the light to complete the exciter circuit in the alternator.
smh00n
Mustang Star
Mustang Star
Posts: 312
Joined: Fri Jan 23, 2015 2:03 pm
Location: Sydney Hills District

Re: Removed the alternator warning light and now it's overchargi

Post by smh00n »

Update. Old alternator was NFG, passing power through at the rate of about .2v per minute. Explains the battery being flat.
Off to Rocket, buy a new 100 amp Aeroflow unit.
Aeroflow alternators may be made for Fords, but not LHD ones. The terminals now sit on the inside of the alternator and the main power stud is about 5mm or less off the block. Be aware if you buy one.

But, it's hooked up and using a 2w bulb I have a light that works. Or doesn't as the case may be.

Pumps out 14v from basically nil revs.
Nuts
Mustang King
Mustang King
Posts: 4635
Joined: Sat Jul 31, 2010 6:07 pm

Re: Removed the alternator warning light and now it's overchargi

Post by Nuts »

Just undo the bolts and rotate the centre and rear to where you want it. Eady done.
My Motto - Don't get Caught! If you do, Blame Someone Else!

MUSTANG - Fantastic Not Plastic
Post Reply