ok so i have the SGII and normally is says my voltage is anywhere from 13.8 to 14.1.
recently i have installed other guages (not sure if this matters)
anyhow now the SGII reads VLTS at 13.4 to 13.6. I am heading to niagara falls next weekend coming anf the sudden drop just made me a bit nervous and wanted to get some opinions on this. If it was due to the recent guages and them being all lit up or why the drop and if its low enough i should worry
Thanks in advance

 

Now my truck goes to 14-14.3Volts right after startup to charge back up after startup and Glow plug warm up.

Now after 10-15 miles it will drop down to 13.4-13.8 volts and hang around there

Also the Alternator will not start to charge untill Glow Plugs turn off so that can be upto the first 2 minutes or so Depending on ambeint temps.

If I was you Id go and thuroly clean ALL Battery cable connections and alternator connections as well as the 2 MAIN Grounds of the negitive sides of Batterys and to where they Mount one by the A/C compressor and the other by the Power steering Pump

Your voltage Does NOT look to bad at all IMO could just be the system was charged up when you took the Voltage reading. IDK from this side of Computer screen

Do you have the Battery Light on dash coming on or on/off???

 

no nothing like a battery ligh tor any other signs. Just had the slight dip in volts i noticed.

 

What Gauges did you Install???

whatever they are I dont see a Backlight on the Gauge causing an issue unless there is a Shorted wire somewhere causing a Battery/Voltage Drain

 

I had just done a set of gauges from Glowshift. fuel presure, oil presure and egt. i also have the sgII

 

Bill from my experiance with my own Alternator and Battery issues that Battery light on the Dash is Right on the Money and will turn on if there is any issues with the charging system be it battery or alternator it turns on.

When my alternator Died it was turning the Dash light on & Off for a long time

When my Batterys Gave out the Light came on but the Batterys didnt Last very long after that light turned on

So Load test Battterys separatly and check Alternator output.

Its also best to have a real Battery load test/Bench Test at autoparts store. And the same goes for alternator output test pull and Bech test. You could test with a DVM but not as Good

 

ok thank you for the info.
i will hi the auto electric place monday morning and check it out for sure. my guess is things are fine now.

 

you can check with a DVM both alternator and Batterys

Thats how I check mine but I also hydro test each Battery cell cuz sometimes a battery will show good voltage and have a weak/bad cell

I also watch my SGII right at startup If the SGII updates at the right time I can see how far Battery volts drop it can range from 10.5-11.5volts but it must update during the Starter Crank and IIRC anything less than 9.6volts at that time is Bad. IMO this is a very Good load test because its the actual Load your throwing at it. But it MUST update during crank so I usually pull up a rpm gauge or something that changes rapidly and watch that and if the number changed during crank I Know SGII updated at the right time and the volt reading will be accurite reading for a Load test.

You will just have to watch it for a few to get the hang of it Because the SGII wont always update during the Crank so set the SGII to Fast Update

You can also check alternator with a DVM but need to do it at Low Idel and again at High Idel make shure volts dont drop off at high idel

Between a SGII and a DVM you can get a Good Idea of charging system health

This is how I do it and if I find anything in question then I pull the Part and get a Bench test at autoparts store

 

Vehicle won't start w/ battery voltage below 9.5V. I get nervous when I see the voltage below 11.5V at first.

 

yes 11.5 volts standing volts would scare me too. IIRC should be right around 12.6 standing voltage

The 10.5-11.6 volts was just the voltage drop I see for that split second when the starter is engauged then it pops right back to 12.0 volts and slowly goes up till GP turns off then hits that 14.0-14.3 charging voltage

All the Ducks must be in a row to even catch it the update Has to be precise

 

I am using am outlook and it never reads higher than 13.2 volts once charged up. Though it never has read below 11.6 cranking either. Just saying, never seen the kinds of high volts at the fuse panel you guys are seeing and inane verified using handgheld At both batteries the high and low voltage. My alt output once charging is always 14.4 sp far, but at the panel where I feed power to outlook it's always 11.7 to 13.2. I think change is more important that actual.....

 

This is form Ed's (FICMRepai.com} web site:

On a 2005 Excursion fitted with the 6.0, a new set of 850CCA Energizer-branded batteries from Sam's Club at a 35° ambient temperature tested out at 12.78 volts at float (after they had been sitting all night), dropped to 12.0 volts during cranking, registered 12.2 volts during the first couple minutes of running while the glow plug circuit was still running (yes, your truck operates on battery alone for up to two minutes EVERY cold start when it's cold outside, which is why short trips are murder on 6.0's batteries), comes up to 14.1 volts while the alternator is working to recharge everything, and ultimately rests at 13.6 volts after the charging cycle is all but complete.

Anything less than these numbers is adding stress to your FICM.

 

mine is close to those numbers. a little less but not much.

 

Since new my 05 has had the outlook, both new and replacement batteries, 12.7 or 12.8 resting, 12.7 cranking, rises to 13.1 once charging, sometimes 13.2. Only time I have ever seen 14s is on the alternator charge.

I am planning on doing some FICM voltage checks here soon. I am thinking she is a bit rough on start. Up despite synthetic oil and warm garage. Ed, how fast can you turn around a FICM from northern BC Canada? Can you send me a rebuilt one based on my VIN with all the bells so I am not down to long, she's a DD.

 

Well I see we will all agree to disagree to a Point LOL its all good
Diffent opinions make it a great thing

now you look at Moefer case right there says his dont ever drop below 12.7volts cranking. His gauges are NOT updating fast enough he not even seeing what I am Talking about.

Hell Moefer had BETTER Numbers than ED (Test on a Brand New Battery LOL) Moefer gauge Just dont catch it he dont see it I can Gaurenty its dropping lower than that 12.7 during crank. I would bet a Buck he Hits in the 11-10volts range. If he could see it. Its there

Now Back to eds Test you Know that voltage only droped to 12 Volts now thats on a Brand Spanking New Battery. Ok Now Fast Forward to the Real World Most Folks Batterys are NOT NEW. To keep up with the Spec of the new Battery in EDS Test a Guy would almost have to drop a New set of Batterys in once a year maybe every other year Ya right not going to happen with me anyway or most folks for that matter

Mine was Load test awhile Back passed heck my alternator was bench tested and Passed (It was BAD) all Battery cells Passed specific gravity test. No Way I was going to get any warrenty on them Batterys. I guess Im saying in the real world 10-11 volts is common volts drop at starter Engauge and not a Big Deal
I would think that a Battery goes downhill from the day its made maybe not much but someVery little by little.