Electrical Dip

[thompsoncustom]

How much electrical dip is normal from turning things on like the headlights or fan? I noticed when I turn anything on it seems to work the system pretty hard. On the voltage gauge just turning the fan on high when idling will move the needle from fluttering right between the red and green down into the yellow. Batteries are group 65 replaced 9/23 so almost new and from what I can tell the alternator is a 200amp dual voltage which is putting out 28.8v to 29v at idle.

 

[Retiredwarhorses]

That doesn’t sound right, while you will see a probably a slight bounce in the gauge initially, the heater blower motor doesn’t have that much amperage draw to leave it sitting in the yellow, it sounds like maybe it’s actually shutting off the regulator from charging, the 200amp regelatos has an over voltage cut off.

 

[thompsoncustom]

sry yes its just a bounce into the yellow it doesn't stay there

 

[MarkM]

I would put a volt meter on the batteries and test it all out. I don't notice any real difference on mine when putting loads on the system. Our gauges are not accurate at all so confirm with a meter.

Mark

 

[Retiredwarhorses]

sry yes its just a bounce into the yellow it doesn't stay there

while running, the needle should be sitting on the white mark in the green….but gauges can be sucky, best to just check for 27.5-28.5 output at idle.

 

[thompsoncustom]

at idle my voltage gauge is always bouncing between the red and green I would say the mid point is where the red and green meet. also at idle at the alternator it's reading 28.8v to 29v but I haven't checked at the batteries.

 

[thompsoncustom]

I would put a volt meter on the batteries and test it all out. I don't notice any real difference on mine when putting loads on the system. Our gauges are not accurate at all so confirm with a meter.

Mark

I should test the batteries individually I suppose there could be a problem there even tho they are newish doesn't mean there good.

 

[FlameRed]

I am no expert, but I recently upgraded from a 60 amp to 200 amp and now mine stays in the middle of the green no matter what accessories or lights, I have on.

As the others said, maybe a loose or corroded connection, regulator going funky, or battery developing a problem.

 

[Retiredwarhorses]

I should test the batteries individually I suppose there could be a problem there even tho they are newish doesn't mean there good.

Yes, a bad or lagging battery will show up on the gauge.

 

[thompsoncustom]

Yes, a bad or lagging battery will show up on the gauge.

something is wrong with the batteries.



I just drove it about an hr ago and the top battery is at 12.3v while the bottom battery is read 13v.

the wires mid way through have me worried not sure if that's right or not but it's how I bought it.

 

[Coug]

Either the regulator is failed, there is a bad connection for the 14V feed from regulator to battery, or the rear (top in your picture) battery is failed/dead.

Here is a link to the manufacturer's troubleshooting guide for the 200 ampalternator.

https://www.ceniehoff.com/Documents/Ctrl_Hyperlink/TG17_uid252021123202.pdf

 

[Mogman]

something is wrong with the batteries.

View attachment 915151

I just drove it about an hr ago and the top battery is at 12.3v while the bottom battery is read 13v.

the wires mid way through have me worried not sure if that's right or not but it's how I bought it.

Test the voltage with the truck running, the voltages you state must be with the truck off.
If they are close to even when running you may have a battery issue, if you do not have a battery load tester any auto parts store can test them.

 

[Mogman]

The way they are connected looks fine.
Do you have a working trans light and if so is it off when the engine is off?

 

[thompsoncustom]

I do have a working trans light and it is off when the engine is off. I will get voltage from the batteries with it running.

 

[MarkM]

Not for anything but you should load test those batteries.. Unless one has a so so connection they should be at the same voltage.

Any idea how old the batteries are? Fully charged with a small load they should settle and hang at 12.5-12.6. You can get a slight over top charge after a recent full charge but that will go away quick and settle at the full charge values. Are these flooded batteries or AGMs?

Mark

 

[thompsoncustom]

Not for anything but you should load test those batteries.. Unless one has a so so connection they should be at the same voltage.

Any idea how old the batteries are? Fully charged with a small load they should settle and hang at 12.5-12.6. You can get a slight over top charge after a recent full charge but that will go away quick and settle at the full charge values. Are these flooded batteries or AGMs?

Mark

I'm gonna pull the batteries tonight and top them off on the charger than tomorrow I'll have them both tested. Batteries are less than 5 months old if one is bad I'll try to have it replaced as it looks to have a 2 year warranty but I didn't purchase them.

Battery specs listed from fleet farm

• Additional exchange fees may apply
• 6572 Supreme Power automotive battery
• 850 Cold Cranking Amps
• Optimal balance of life, power & durability
• Optimized power plates
• 72 month warranty with 24 month free replacement
• Weight: Approximately: 46.5 pounds
• Shipping Dimensions: Approximately 11 x 8 x 7.25 inches.

Test the voltage with the truck running, the voltages you state must be with the truck off.
If they are close to even when running you may have a battery issue, if you do not have a battery load tester any auto parts store can test them.

Let the truck ran for about 30 mins and than run it up and down the road than tested the batteries with it running. Top battery is the photo tested at 12.40v and the bottom battery tested at 14.30v

 

[Mogman]

I'm gonna pull the batteries tonight and top them off on the charger than tomorrow I'll have them both tested. Batteries are less than 5 months old if one is bad I'll try to have it replaced as it looks to have a 2 year warranty but I didn't purchase them.

Battery specs listed from fleet farm

• Additional exchange fees may apply
• 6572 Supreme Power automotive battery
• 850 Cold Cranking Amps
• Optimal balance of life, power & durability
• Optimized power plates
• 72 month warranty with 24 month free replacement
• Weight: Approximately: 46.5 pounds
• Shipping Dimensions: Approximately 11 x 8 x 7.25 inches.

Let the truck ran for about 30 mins and than run it up and down the road than tested the batteries with it running. Top battery is the photo tested at 12.40v and the bottom battery tested at 14.30v

Since you have the batteries out after you get them load tested put them in in the opposite position they were originally in, if they check out OK.
It looks like the alt is under charging at 26.7V but get the batts tested first then go back and look at the charging voltage.
Check the voltages at the alt 28V and 14V posts and compare it to the battery voltages.

 

[thompsoncustom]

Since you have the batteries out after you get them load tested put them in in the opposite position they were originally in, if they check out OK.
It looks like the alt is under charging at 26.7V but get the batts tested first then go back and look at the charging voltage.
Check the voltages at the alt 28V and 14V posts and compare it to the battery voltages.

Had both batteries tested this morning and both checked out good. the lower voltage one had 940cca and the higher voltage one had 1050cca both were warm and charged last night.

swap the battery positions in the box and drove it around this morning and checked them again with the humvee running and got 13.1v on the one closest to the hood and 13.6v on the one closest to the rear.

at the alternator I'm getting 28.8v from the 24v side. Both of the little post on the regulator give me 17.7v and the big post on front of the regulator and the red little post give me 13.1v

 

[Mogman]

It would be helpful to give the wire tag numbers/post ID on the connections you are quoting on the regulator, you seem to be seeing one more post than I remember.
You should have much closer to 26V on the IGN/Sense (wire tag 5A) the larger of the two small posts on the reg.
Check it again with the fan on high. (this will put more load on the relay in the PCB/EESS box)
You also should check (loosen clean and re-torque) all the heavy cables (pos and neg) from the starter (ground) to the battery box to the alt.
It looks like you have a 2.1V drop between the alt and the batteries which is too much.
Do not re-torque the batt positive and the solenoid as it is easy to break the plastic solenoid and the currents we are talking about should not be passing through that connection, also check the ground connection to the alt.
There are pos and neg connections on both sides of the battery box pass through bulkhead connectors.
Of course disconnect the batteries first.

 

[thompsoncustom]

looking at the metal tags between 2a and 568 is where I get 17.7v and between 568 and 68a is where a get 13.1 all on the regulator.

I cleaned most of the vehicle grounds when I got it including the one on the alt and starter but I'll look over all the connections a little more.