My alternator is charging at 1,500 rpm between 14.7 and 15.5 volts?
I think that may be too much?
Bangkok Dean
07-07-2017, 07:16 AM
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Normal range should be about 13.8-14.4. 14.8 is a little high and 15.5 is definitely too high. These are the numbers I have always had produced by either the stock 12SI 63 amp alternator, 12SI 120 amp alternator (on the car for about 15 years before the switch) and my current CS144 140 amp alternator. all verified with a voltmeter off the battery and alternator. I would not rely on the dash voltmeter for your readings.
Have you checked the volt readings with a voltmeter? You should also see higher voltage readings immediately after startup since the battery was drained turning the starter and slightly lower voltage readings with a high electrical load with accessories pulling amps.
07-07-2017, 08:06 AM
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Yes I have checked with a voltmeter it is the same as the gauge.. Right after starting there is no voltage increases until I rev it to 1,500 then it mostly stays around 15 volts to 15.5 volts, even at idle.
Last edited by Bangkok Dean; 07-07-2017 at 08:08 AM .
Bangkok Dean
07-07-2017, 09:09 AM
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Voltage regulator in the alternator. new or old alternator. if new bring it back
07-07-2017, 09:49 AM
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Původně odeslal Bangkok Dean
My alternator is charging at 1,500 rpm between 14.7 and 15.5 volts?
I think that may be too much?
Long time old friend. Regulator is shot.
07-08-2017, 02:28 AM
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Původně odeslal jb78L-82
Voltage regulator in the alternator. new or old alternator. if new bring it back
Původně odeslal Big2Bird
Long time old friend. Regulator is shot.
Thanks for the replies, First in Thailand there is no taking it back. lol
I have just installed a used regulator that is good. now it is 14 volts.
Na zdraví
Last edited by Bangkok Dean; 07-08-2017 at 06:34 AM .
Bangkok Dean
07-08-2017, 11:45 AM
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Donor St. Jude ’15
Last edited by bruiser; 07-08-2017 at 11:46 AM .
07-08-2017, 07:06 PM
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Max. charging voltage on most car alternators is in the 14.5 volt range. If the voltage regulator (whether in the alternator or not) is not sensing the output voltage properly, it could be driving to regulate as if the battery were fully depleted. Or, your battery COULD be fully discharged.
If the battery is fully charged, the alternator voltage should not be over 13 volts.
07-09-2017, 12:53 AM
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Původně odeslal 7T1vette
Max. charging voltage on most car alternators is in the 14.5 volt range. If the voltage regulator (whether in the alternator or not) is not sensing the output voltage properly, it could be driving to regulate as if the battery were fully depleted. Or, your battery COULD be fully discharged.
If the battery is fully charged, the alternator voltage should not be over 13 volts.
Unfortunately it is monsoon season so I am unable to go for a good drive to see what it settles in at. But from all those that have chimed in 14 volts @1,500rpm is better than 15.5volts.
If it ever stops raining I will see what happens.
Bangkok Dean
07-09-2017, 07:31 AM
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Zkusme to znovu.
The normal voltage for an alternator charging is between 13.8-14.4 volts like I stated above, depending on temp outside, accessory load, how depleted the battery is, etc (like starting the car). These numbers can be higher under certain conditions. read the below link..
Normal battery voltage for a fully charged battery is 12.6 volts. In a car with a fully charged battery and no accessories running, the alternator voltage will be 13.3-13.4 volts. In this situation, the alternator voltage should never be less than 13 volts!
Last edited by jb78L-82; 07-09-2017 at 07:33 AM .
07-09-2017, 11:40 AM
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Původně odeslal Bangkok Dean
Unfortunately it is monsoon season so I am unable to go for a good drive to see what it settles in at. But from all those that have chimed in 14 volts @1,500rpm is better than 15.5volts.
If it ever stops raining I will see what happens.
Yes, 14 volts is much better than the 15.5. Normal charging is usually 1 volt over a fully charged battery (12.6) up to 15.5 volts. The 15.5 is the max output and is rarely seen unless the battery has run down. You may seen that max 15.5 for a short time, but then it should settle down. Since yours stayed at the 15.5, its the regulator in the alternator. Depending on the state of the battery and the accessories that are on, between 13.5v and 14v are average numbers. Newer cars with their multitude of computers and electronics usually run closer to the 14 and slightly above that (idle). Stay dry.
I have replaced both the Battery (Duracel AGM) and the Alternator (Bosch reman) on my 2005 Escalade ESV (6.0 liter engine). After driving for a while, meter measured Voltage output just above 15.2 volts. Reader says this is High. I do live at 7500 feet elevation (don’t think this matters, but you never know). Any ideas of what could be causing this? Shouldn’t reading be around 14.3 — 14.8?
1751 příspěvků · Připojeno 2016
Probably a defective alternator.
2006 Escalade AWD s díly Jet Performance, výkonným vzduchovým filtrem AFE Dry a sáním Airaid MIT Diablo Sport vyladěné pro zvýšení výkonu. 0-60 mph za 6.5 sekundy. řekl Nuff.
Pdbille Discussion starter
9 příspěvků · Připojeno 2021
Sorry, should have been more clear. Battery tested low, so I replaced it. Charging system was at 15+ on the old alternator. So I replaced that. Looking to see what I am missing. Not sure if my vehicle has external voltage regulator (from the alternator).
1751 příspěvků · Připojeno 2016
You were pretty clear. My point is the re-manufactured alternator is probably the issue. It probably has a bad voltage regulator. Re-manufactured is not the same as new, so it could still be a dud and needs to be replaced under warranty.
2006 Escalade AWD s díly Jet Performance, výkonným vzduchovým filtrem AFE Dry a sáním Airaid MIT Diablo Sport vyladěné pro zvýšení výkonu. 0-60 mph za 6.5 sekundy. řekl Nuff.
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161 příspěvků · Připojeno 2018
Your vehicle regulates the voltage via the BCM & PCM, sending a signal to one of the wires in the 2 pin connector at the back of the alternator. If you disconnect the 2 pin plug on alternator, it should then self regulate to 13.7-13.8 Volts. It is a good diagnostic test to disconnect that plug, and then see what happens to the voltage.
Pdbille Discussion starter
9 příspěvků · Připojeno 2021
Thanks, I did see some info about that online. Did not realize the vehicle had RVC. Whole new set of trouble shooting I can do. Will check it with the sensor disconnected to see what I get.
824 příspěvků · Připojeno 2019
On some vehicles and I don’t know if yours is one of them You have to go in with a programmer or scanner and tell the computer that you have put a new battery in because with old battery they have to be charged at a higher voltage and the new ones don’t.If you don’t tell the ECM about the new battery it will continue to charge at the voltage it was using for the old battery. And not sure if this is the sensor for that or not but you might look into this part:
2005 CADILLAC ESCALADE 6.0L V8 Generator Battery Control Module | RockAuto
RockAuto dodává autodíly a díly karoserie od více než 300 výrobců až k zákazníkům po celém světě, vše za skladové ceny. Snadno použitelný katalog dílů.
www.rockauto.com
Pdbille Discussion starter
9 příspěvků · Připojeno 2021
Thanks Roy, I did find this part. It is connected to the negative battery cable. I believe it is the next step in my trouble shooting, Hard to find, most places are out of stock, and GM says no longer available. I did find one online. Beginning to wonder if I can just bypass this module. Looking at the notes this SARVC is the RVC version for my vehicle. According to GM Tech notes,
This unit does not use the BCM for operation. Also states «This module also directly controls the generator L-terminal dutycycle instead of the ECM/PCM»
4 příspěvků · Připojeno 2020
Where did you find the replacement one you ordered?
161 příspěvků · Připojeno 2018
Yes, you are correct. The ECM / BCM control is 2007 & Up. Do the disconnect test to see what voltage you get. There is also a great controller available that you can plug into the alternator, and it will give you a constant 14.8V (or adjustable for extra cost), and not set any trouble codes. With this controller plugged in, the alternator control signal from the battery control module is no longer connected to the alternator. US Alternators GM-PCM
1270 příspěvků · Připojeno 2014
Are you reading the voltage on the dash which can give false info or are you using a digital voltmeter?
I’ve never seen one with chrome letters on it that says BASE or SHORTY.
Pdbille Discussion starter
9 příspěvků · Připojeno 2021
Yes using voltmeter. (actually the dashboard dial, is really close. That is what alerted me in the first place)
10947 příspěvků · Připojeno 2006
You probably didn’t need to replace the alternator.
Pdbille Discussion starter
9 příspěvků · Připojeno 2021
Agree, waiting until I replace SARVC, once I get the part.
11917 příspěvků · Připojeno 2011
Get the “new” battery load tested.
I’ll bet it will test out bad.
I’ve had this happen before.
The alternator in these trucks are pretty good and rarely fail unless they are overloaded.
The voltage gauge going up to 15 volts pretty much means your truck is basically running mostly on the alternator since the battery isn’t likely taking a charge.
Don’t forget to check the connections as they are notorious for corrosion on these trucks.
1 příspěvek · Připojeno 2021
I have a 2013 XTS new to me, it has 120k, the battery failed to start car two times over this winter. Months apart. I have watched the dash readout 11.3 just after it starts then goes to 14. something. Within 5 minutes driving it reads 15.0 — 15.2. I was going to replace the battery later this year. Sound similar to last Recommending replacing asap? Drop in a new battery and off to the races or is there some kind of programing involved?
Díky
824 příspěvků · Připojeno 2019
Get a digital voltmeter and test the battery. Just sitting there it should not be below 12.4. Running it should be somewhere around 14.4. If it is not 99% chance your battery is bad. When you change your battery try to get a memory minder and if you have another car that you can pull up fairly close to it get one like this:
You can Google memory minder and pick one you like but make sure it has a long enough cable to go from 1 car to another or you have a battery to put on the floor inside the car to connect to when you change the battery.
2363 příspěvků · Připojeno 2018
AGM batteries need to be charged to 90-100%, most are less than 75%, some even 50%. Otherwise your alternator will work like crazy to get it charged up.
Pdbille Discussion starter
9 příspěvků · Připojeno 2021
OK so I believe I have isolated it to the Stand Alone Regulated Voltage Control (SARVC) module. When I disconnected the module, battery was at 12.8 volts. and alternator was charging at 13.7 volts. Obviously with this disconnected it was throwing a charging system error to the dashboard. Just waiting on the part to be delivered.
So to recap for everyone. This all started with a dying battery. Battery was 4+ years old was only charging to about 11.3volts. At the same time I noticed that the alternator was starting to push a little over 15Volts after warmup. I replaced the battery (with a new AMG battery with a manufacture date of 3/21, yes less than a month old). Battery was fine, but the alternator continued to charge at 15+volts after warmup. I then replaced the alternator. Yet it continued to charge at 15+volts. I then found out through research the my vehicle has a SARVC module. This module is attached to the negative cable off of the battery and communicates with the BCM&PCM. SO I am hoping that the SARVC is the issue and not something with the BCM or PCM.
