Alternator charging too much?

[LVJJJ]

Stupid again. While removing all of the stock radio and cassette components to install a new radio, I did not disconnect the battery right away. After removing the amp/tuner I finally did. As far as I know, I didn't short out any wires except for my LED running lights, but the fuse blew immediately so don't think that did anything. Now when driving, the alternator is charging just over 14 amps when starting and driving for a little while, I checked it out with a multimeter. Then it drops a little after a while, probably around 13.5, haven't measured that yet. Then dropped to probably 12 volts when it warms up. When turning on headlites it drops a little more.

Before the guage was not registering that high, maybe 13.5? Never checked it, everything was working fine. I'm wondering if the computer controls the charging system? What would cause it to charge more, seems like it had to do with my working on the wiring with the battery hooked up? I'm afraid overcharging will ruin the battery. Alternator was new a couple of years ago, battery new about 4 years ago.

As for the new JVC radio, been trying to set it up with little luck. So I bought an old Jensen Cassette radio for $5 at a thrift store (Wacky Warehouse in Pacific Beach WA). I found that you can get two prong adaptors for the radio hole so I plan to order one of those and install the Jensen instead. since there probably won't be much bass, I've got an old Craig booster 9 band EQ I'll add below the dash, that should take care of it (got it for $10). I really miss being able to adjust the volume with a knob, adjust the balance with a knob, adjust the treble-bass with a knob, move station to station with a knob, etc. etc.

 

[LVJJJ]

Had dinner with a son-in-law who is a computer expert. He mentioned that the new JVC radio probably requires a lot more electrical power to work than the stock radio, so the higher charging rate might be caused by this? Makes sense as it started right when I installed the radio. I'm probably paranoid, everything still working ok.

 

[Erik the Awful]

Now I'm wondering what the censored word is. Did the forum censor the word nerd?

Edit: Nope. Hmm...

 

[Nad_Yvalhosert]

Now when driving, the alternator is charging just over 14 amps when starting and driving for a little while, I checked it out with a multimeter. Then it drops a little after a while, probably around 13.5, haven't measured that yet.

Only 14 amps? My Suburban's alternator is a 105 Amp, and I've got the 140 amp in my Yukon Denali.
How'd you measure amperage?

 

[Nad_Yvalhosert]

Oh, you mean voltage. 14 is good, 13.5 is OK. Honestly, depending on electrical load, 13.2 to 14.6 is totally normal.

If I were you, I'd check voltage at the output stud on the alternator, and on the battery terminals before trusting the gauge on the dash.

 

[GoToGuy]

So now your " gun shy" after refresher lesson on why you disconnect battery ground before electrcal work. After starting the battery will have drawn down, resulting in alternator higher output to charge battery and supply other demands. Don't guess with electrical. Get a decent multimeter if your going do this kind of work. Good luck.

 

[LVJJJ]

Haven't been watching this forum so a little late reply here. Thanks for the responses, 'specially Nad, makes me feel better.

I did check the battery with a multimeter when first starting and it was around 14.5. Then drops down below the 14 mark. I don't trust the guages on the dash either, but they are a good general indicator.

I know I'm supposed to disconnect the battery when working on electrical, but I started the job under the steering wheel and dash and just didn't want to wiggle back out, hard enough getting down there (am 75, everything is more difficult). Finally did disconnect when had to back out and get one of the many tools I forgot. But seems like i didn't hurt anything.

 

[GoToGuy]

I hear you, when did i turn 64 ?

 

[Frank Enstein]

The gauges lie like rugs. They are like idiot lights with needles. They only read NORMAL and NOT NORMAL.

As long as it reads right on the battery you're fine. I may try to make mine a bit better the next time I have the cluster out by popping off the needle and reinstalling using the voltmeter on the battery so it's accurate at NORMAL!

 

[AuroraGirl]

what year is your truck
95/96 trucks got a cs130d and 99 got ad230 and both of those alternators have more intelligent internal "brains" and also how are your charge cables. if your charge wire is really resistive, your cable connections are corroded, you could be putting out juice because its fighting voltage drop somewhere or the "demand" is causing a need to output depending on how things are