-
You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
Strange
- Thread starter Ziploc
- Start date
So I never really took notice , maybe truly my xterra charging system can’t handle my comp radio and 2 pill. I check my ground yesterday 0.2 at seat bolt , probes together same reading. Long story short when I’m on the move I have ZERO issues as I described at idle . Also my linc 2 plus shows at idle 14.3 volts while on the move key up modulate with amp on it’s never once went below 13.8 14.0 on avg. now at idle remember it’s freezing here so heater on lights on basic load at idle I key up and it 12.8 while modulating, however it catches up and goes back to normal. All this time maybe I do truly have a charging system not adaquet for me at idle ????? Thoughts
Ok, then, you want more?
Go Here...
Smart Charging Systems | Second Generation Nissan Xterra Forums (thenewx.org)
Read Response #5
Then loop back to your thread about Idle volts, should make more sense
Go Here...
Smart Charging Systems | Second Generation Nissan Xterra Forums (thenewx.org)
Read Response #5
Then loop back to your thread about Idle volts, should make more sense
Andy , so your saying this is normal for what I’m describing with the xterra at idle ? No way around this variable voltage regulator on the negative cable ?
I hope you can understand this diagram.
For if you don't - then you may need to read your vehicle's OWNERS MANUAL for next time...
They (Nissan) use a Comparator to generate a differential output that the PCM then uses to boost or reduce charge rate by looking at the potentials between BODY (Chassis) and Engine Block - when Frame current demand goes up the difference is sent to the PCM to boost alternator output - when demand drops, the PCM doesn't ask the Alternator to produce as much
Due to the newer technology in kinds of butleries, plus their wide variety you can use, the system monitors more of the Frame and Engine needs than the Battery - this lessens the charging swings for the Battery - it simply acts like a load all the time, so the PCM does the decision making - not the Regulator - it's been put in the ECM on Nissans post - 2015...
When you're at Idle, and key up the linear, the system needs to boost the voltage so it should kick up idle - if it isn't then the system is not sensing the load because the system doesn't see a "secondary feed" from the powered system, a Demand line - on the PCM monitor line.
I used to own a 2005 Scion - miss that car, for as basic as it was and simple to service - it's why it had 200,000+ Miles on it before the XYL blew up one day and told me to get rid of it - she bought a Nissan - so yes, I know how, and Yes, we've gone thru 2 batteries, and 4 recalls for various un-investigated - reasons they WON'T tell you.
Do I wish for the old days?, (Gosh Darn) D*mn right I Do! But I know they "ain't coming back" for the kids these days are brainwashed - we, older more experienced folks are on the losing side of this because the brainwashing is telling todays younger people the wrong stuff - it works because it fits their facts not our experiences in history nor in learning.
They just rewrite it - So stay tuned..
For if you don't - then you may need to read your vehicle's OWNERS MANUAL for next time...
They (Nissan) use a Comparator to generate a differential output that the PCM then uses to boost or reduce charge rate by looking at the potentials between BODY (Chassis) and Engine Block - when Frame current demand goes up the difference is sent to the PCM to boost alternator output - when demand drops, the PCM doesn't ask the Alternator to produce as much
Due to the newer technology in kinds of butleries, plus their wide variety you can use, the system monitors more of the Frame and Engine needs than the Battery - this lessens the charging swings for the Battery - it simply acts like a load all the time, so the PCM does the decision making - not the Regulator - it's been put in the ECM on Nissans post - 2015...
When you're at Idle, and key up the linear, the system needs to boost the voltage so it should kick up idle - if it isn't then the system is not sensing the load because the system doesn't see a "secondary feed" from the powered system, a Demand line - on the PCM monitor line.
- Go back to Idle Volts - what I said back in Idle Volts thread pertains to this, for most systems are SMART enough to see a battery needs charging,
- - but are not intuitive to know what you're trying to run
- - so you need a "presence" wire that tells the system something is powered up and will need current demand
- A/C and Blower heater systems have a "presence" wire that goes into the PCM monitor harness feeds - they tell the system an accessory is on and it will demand power - so the PCM monitors the charging system more thru an increase in sensitivity in a feedback loop monitor it sees the battery and Frame grounds as - instead of Engine block ground which runs it's own demands. It always tries to save a little for the Battery for it too monitors it's condition and if it thinks it's going to fail - it will set a trouble code DTC and a light on the Dash.
- Example- like your "ALT" light in older systems ran a field wire to the Rotor to "excite" the Regulator to boost more power thru that bulb, when the belt or regulator failed - the ALT light lit up because now the battery was running into the Exciter - not the Alternators Trio to the Rotor - in other words, no Alternator output was occurring
I used to own a 2005 Scion - miss that car, for as basic as it was and simple to service - it's why it had 200,000+ Miles on it before the XYL blew up one day and told me to get rid of it - she bought a Nissan - so yes, I know how, and Yes, we've gone thru 2 batteries, and 4 recalls for various un-investigated - reasons they WON'T tell you.
Do I wish for the old days?, (Gosh Darn) D*mn right I Do! But I know they "ain't coming back" for the kids these days are brainwashed - we, older more experienced folks are on the losing side of this because the brainwashing is telling todays younger people the wrong stuff - it works because it fits their facts not our experiences in history nor in learning.
They just rewrite it - So stay tuned..
Last edited:
You may also just have to face the fact that the alternator is just to small. Im assuming its like a 110a at best. So take half of that away to run the car, add radio gear and amplifier , doesnt leave much headroom. Plus alternators never put out their rated amperage at idle. Usually like a quarter of the rating which is one reason you are having issues. Look at keydown vids. There is a reason we rev the motors up on keydown.
Yes and my fusion 3.0 2010 has a 160 amp lol maybe swapping cars with wife . I’m sure 110 xterra and 160 fusion would be a upgrade.
Years ago there was a similarly long thread on the forum on how to ground an amp so it will not cause the vehicle's ECM to have problems. I believe it was LOOSECANNON who was having the problem. The consensus answer was that ground loops were the cause of the ECM's fluctuations, and to prevent these loops, the CB amp ground should be connected to the point where the negative battery cable is connected (i.e. frame, body, engine block, whatever.) The cb amp positive should be connected to the positive post on the battery. This way, the CB's electrical system is totally separate from the vehicle's system. A good rule of thumb is the hookup wire should be one gauge larger than the amp builder specifies.
New vehicles are pretty much self-powered computers and the sensors are easily affected by large RF fields. Getting a high powered CB or amateur radio system to work in today's vehicles requires much thought and good engineering.
- 399
New vehicles are pretty much self-powered computers and the sensors are easily affected by large RF fields. Getting a high powered CB or amateur radio system to work in today's vehicles requires much thought and good engineering.
- 399
Also worth mentioning, don’t use dielectric grease. Use Naolox or something similar. This is a conductive grease that prohibits corrosion.
Remember too, the newer Battery Technology allows for more amps per cell - they changed the way it's made, more plates thinner dielectric - so more capacity.
The problem is, the specific gravity of the Acid (Electrolyte) is still the same old lead-acid stuff with some minor minerals added that reduce the corrosivity and the low-temperature recombination (icing) in extreme cold.
It looks like a different type of resistor/impedance now - and older system would throw 20 amps all the time whether the battery needs it or not because of the load the battery puts on the system due to this change/upgrade - the older charging systems would overcharge the battery quite easily - or at least make it produce gas until it's boiled dry.
I've seen Delco- Remy battery in my old Tracker boil away at the Truckstop off of I-65 in Tennessee because of altitude and the charging system needed an older battery style to work properly - had that explained to me at a repair shop - in no certain terms - and the hit against the wallet.
The problem is, the specific gravity of the Acid (Electrolyte) is still the same old lead-acid stuff with some minor minerals added that reduce the corrosivity and the low-temperature recombination (icing) in extreme cold.
It looks like a different type of resistor/impedance now - and older system would throw 20 amps all the time whether the battery needs it or not because of the load the battery puts on the system due to this change/upgrade - the older charging systems would overcharge the battery quite easily - or at least make it produce gas until it's boiled dry.
I've seen Delco- Remy battery in my old Tracker boil away at the Truckstop off of I-65 in Tennessee because of altitude and the charging system needed an older battery style to work properly - had that explained to me at a repair shop - in no certain terms - and the hit against the wallet.
I thank you all for all the help. Handy Andy didn’t give up on this and actually figured it out. Long story short Nissan has a variable voltage regulator on negative battery cable . So it talks back and forth to the alternator bla bla bla . So you all know knock on wood I have zero issues on the move just at idle. Weird as hell Andy suggested to sit idle in neutral with AC on and try key radio and amp and start modulating ::::::: absolutely no movement from battery gauge and I heard something kicking on and off , no it wasn’t the ac clutch well that to but I felt like something in my motor was calling for more juice . Andy knows his crap . Thank you all
Good to see a happy ending.
As long as we are here......
I have one question, and it is the part about
" something kicking on and off "
(I know very little about your vehicle.)
Is it possible that when the ECU see's a voltage drop at the battery , while at idle , it "should" trigger a high idle pull up?
I know that
On some AC systems if the engine is at idle and the clutch on the AC compressor engages, the ECU will increase the idle speed to allow the system to work properly.
This is a question for anyone that knows this vehicle's charging system.
73
Jeff
As long as we are here......
I have one question, and it is the part about
" something kicking on and off "
(I know very little about your vehicle.)
Is it possible that when the ECU see's a voltage drop at the battery , while at idle , it "should" trigger a high idle pull up?
I know that
On some AC systems if the engine is at idle and the clutch on the AC compressor engages, the ECU will increase the idle speed to allow the system to work properly.
This is a question for anyone that knows this vehicle's charging system.
73
Jeff