Charging light comes on and shows?????

Jerbearyukon · Post by **Jerbearyukon** » Tue Mar 18, 2008 12:36 am

only 23.4 volt charging at batteries. Stays on for about 3/4 of and hour on three seperate trips . Then I start her and no light. Check charge at batteries and it's 28.3 volts

. Anyone know what's going on here. I keep waiting to have dead batteries but so far she has been starting ok.

Jer Bear

Anthony · Post by **Anthony** » Tue Mar 18, 2008 4:18 am

Have you checked the Voltage of each individual battery while they are disconnected?

Jim LaGuardia · Post by **Jim LaGuardia** » Tue Mar 18, 2008 5:47 am

Try looking at the Molex connector, it will be corroded. You must check both ends, that means lift the front engine tin to inspect properly

Erik712m · Post by **Erik712m** » Tue Mar 18, 2008 11:29 am

[quote]Try looking at the Molex connector[/quote] Jim, it seems that this is a problem alot. have you guys came up with a replacement? some thing water tyte.

Jerbearyukon · Post by **Jerbearyukon** » Tue Mar 18, 2008 11:54 am

Ok so I have pulled the molex - it was a bit dirty - cleaned it up and put the anti oxidant grease in it. Checked behind the cowling and everything is tight there. Checked the relay under the heat ducting (no this could have a better spot to be I would think and I may move it later. It was iffy so I pulled it and cleaned it all up. Then Dennis suggested to pull the regulator and clean the back of it and make sure it is making good contact to ground with it's frame (have to do this now).

I will let you know what the results are

MarkPinz · Post by **MarkPinz** » Tue Mar 18, 2008 9:45 pm

My Pinz had charging probs from day one

Taking Jim's advice the Molex visually looked OK. Upon closer inspection the female connector for the red wire had been hack / re-cramped back together. It was holding on by a single strand of wire & arching. Re- stripped the wire with new female & finally obtained the correct charging rate

Jerbearyukon · Post by **Jerbearyukon** » Tue Mar 18, 2008 10:12 pm

So what do you get at the battery terminals and how do you check the current out of the alternator

. You see I am an electrician but I HATE DC. there are so many things that go wrong with DC. bad grounds moving parts etc. Then try to trouble shoot.

Anyway we are all about CURRENT. I want to see what CURRENT is coming out and everyone tells me "oh just check to see that you have around 27.5 - 28 volts at the battery terminals and your good. BUT it's the current that charges the batteries and you just need enough voltage to overcome the voltage of the batteries.

Sorry to rant. I just can't seemed to find a clip on DC ammeter than doesn't cost you your left arm and right nut

Jer Bear

Jimm391730 · Post by **Jimm391730** » Tue Mar 18, 2008 11:24 pm

I just can't seemed to find a clip on DC ammeter than doesn't cost you your left arm and right nut

If you are worried about the current, go to any automotive store and buy a cheap dashmounted ammeter. Disconnect one lead to one battery (doesn't matter which of the four leads) and temporarily hold the ammeter to complete the connection (you can use spring clips to hold it together for a test).

But the voltmeter is the proper way to go. If the batteries are getting 27-28V (13-14V per battery) they are getting all the current they need. If this happens while the lights are on, the fan, and the wipers, you have all the current a stock truck needs. Pull too much current (lots of lights, etc.) and the alternator can't supply enough current and the voltage to the batteries starts to fall.

I've seen at least one truck where the voltage regulator failed and the batteries were ruined by overcharging. A current meter would show a great charging curent, but without seeing the 32-35V that the batteries were getting you couldn't tell how bad things were. We were comming out of Death Valley just about sunset and noticed "smells", turns out the batteries were boiled DRY!!! Fortunately had water to fill the batteries (over a gallon for each battery!) and rinse out the compartment. Adding water gave the system something to "work into" and allowed us to make the 6 hour drive home without further incident (sans replacing the batteries later).

One of my trucks has a digital voltmeter that I installed into the Tach opening, in the other truck I use my Garmin GPS that can not only run from 8-32 volts but has a voltmeter display (and can program a "low voltage" warning, too). Handy in alot of ways.

Jim M.
712W and 710M

Jerbearyukon · Post by **Jerbearyukon** » Tue Mar 18, 2008 11:31 pm

thanks a bunch. I will get on it. Dennis is sending me some stuff and a new regulator as a back up. I will check the stuff this weekend (4 days off yeah)

Jer Bear

Jimm391730 · Post by **Jimm391730** » Tue Mar 18, 2008 11:44 pm

I've had our two trucks for a combined total of 11 years, and the ONLY charging probem issues has ALWAYS been the damn Molex connector through the air ducting tin. Usually the wire corrodes on the inside of the tin, back in the plastic connector where it's darn difficult to see. When I've fixed mine I've used liberal amounts of De-ox compound (basically just grease) to help protect the bare wire, the crimp, and the actual connector junction from corrosion. Once done properly it's probably good for many years, but without corrosion protection it is a problem waiting to happen.

Because of that connector failure (and the fact that even though I knew to check it, I was too lazy to do so) it once caused the alternator rotor to fry, requireing a complete alternator replacement (can you say HUNDREDS of dollars?!). Learned my lesson the hard way. However, now with the voltmeters to keep tabs on things I've never been stranded nor caused more serious damage than just getting the connection fixed.

Jim M.

Jerbearyukon · Post by **Jerbearyukon** » Thu Mar 20, 2008 4:11 pm

okie dokie I will check the alternator side - I have re-dne the otherside.

So last night it was in lightning bolt mode - NOT CHARGING - This morning a fairy must have jumped in ahead of me adn the fairy must be a wrench. Barely started and it finally caught and started up. Bingo NO LIGHT...and charging at 27.9 volts.....WIERD

Jer Bear

Jimm391730 · Post by **Jimm391730** » Thu Mar 20, 2008 5:01 pm

Also check how snug the actual mating portions of the connectors are, I've seen them "loosen" so the male portion is not tight in the female connector. I've had to slighly crimp the female to tighen it back up. Check all of the connections for this issue, too.

Jim M.

Twin Pinzies · Post by **Twin Pinzies** » Sat Mar 22, 2008 5:53 pm

I just replaced my alternator and voltage converter. Now the charge light goes on and off during driving. What's that all about?

Jerbearyukon · Post by **Jerbearyukon** » Sat Mar 22, 2008 9:20 pm

not sure about the light going on and off

BUT I found the culprit after following a lead from Dennis "the un-menace"

.

Should I run another contest????hmmmmmmmmmmm what could it have been - A clue is that I hate DC.

Jer Bear

Jim LaGuardia · Post by **Jim LaGuardia** » Sat Mar 22, 2008 9:24 pm

Could be many things, start at the source and work your way to each connection, and make sure the belt is adjusted and idle is between 850-950 rpm. Loose connection at the starter lug is another place to check.