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Technical Electrical Issue - Dimming lights and humming

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Technical Electrical Issue - Dimming lights and humming

everson38
Sorry to hear you did not do a battery check at a local shop.
This will help in deducing a bad battery.
You drained the battery so much that it ended in all kinds of failures and error messages.
This can also damage the battery even more.
My suggestion:
charge battery overnight, drive to a shop where you can test the battery.
CCA measure and internal resistance will give an idea of battery condition.
If all looks sufficient then testing and measuring under load will be the next steps to find possible bad earth connections or alternator failure.
 
Bernievarian said:
Hi Emerson,

this sounds like a dead battery ! One cell should be 2,1v when charged, this is 12,6v when 6 of them are in serie. Your reading is below that, meaning the battery pack is not charged. After one hour or so of charging, the tension reaches a "normal" level, but it's not true: as soon as you will drain some current out of it the tension will collapse. The "no drop" you noticed between post and connector is because you're not draining any current (contact off), that doesn't mean the connection is good: you should measure the drop whilst draining huge current !

Anyway, looking forward for your tomorrow's update ...

edit: battery voltage is not EXACTLY reflecting its charge status: when discharging it stays almost at 2,0v (per cell) untill it gets quite low in capacity when the potential (voltage) will drop severely ...

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)
Click to expand...
Her Berne. Thanks fir the advice. I agree with you in the battery. As i went back out to the to check the battery. Now it had been on charge for about 4 hours and it read 12.34 volts. But when i turned off the power from my charger and read the voltage via multimeter it began dropping like a stopwatch. Im still going to give it a full nights charge to just diagnose full, but it seems as soon as its off charge it begin to fall.

Whilst i have you. If i do need to change battery i want to go one that can put up with my style of driving and dormantcy (short trips and not used for about 4 days out of the week). Ive done some research, is it best to go to a bigger CCA? Currently im on 40ah and 400cca. Will upgrading pose any issues and how far should i go?
 
damted said:
everson38
Sorry to hear you did not do a battery check at a local shop.
This will help in deducing a bad battery.
You drained the battery so much that it ended in all kinds of failures and error messages.
This can also damage the battery even more.
My suggestion:
charge battery overnight, drive to a shop where you can test the battery.
CCA measure and internal resistance will give an idea of battery condition.
If all looks sufficient then testing and measuring under load will be the next steps to find possible bad earth connections or alternator failure.
Click to expand...
Dmhey damted. I did think me load testing just the battery may of.pushed it over the end, but surely the battery was on its way out then, as sitting in your car with those accesories on for 30 seconds wouldnt drain out a good / new battery in that fast manner? But yes that is my jext step. It is currently charging, but i did check it earlier and it was at 12.37 volts, but when i turned off the charger the volts began dropping like a timer, so i believe the battery may get me there to halfords hut i worry once i turn my car off, the battery could go completely dead on me.
 
Hi Emerson,

you can install a larger battery as far as it fits in the tray but compare it to the gas tank: if you burn 1 galon of fuel every day of the week and refill only 5 galons every monday, you'll finally got a dry tank ! No matter how big it is ...

The best way would be to fill more gas each monday, i.e: a bigger alternator !
As I believe you won't go for such a drastic solution, I suggest you hook a battery optimizer on it when the car is stucked in the garage. (10ish £ @ Lidl)

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)
 
Last edited:
Hey guys. So ive been to halfords and i'm just unsure where to go. I have done a video to explain where I am at. But definitely more research is needed. I would appreciate giving the video a watch and then ill try answer any questions. Also apologies for video being in portrait mode,if your turn 'rotate screen' off on your phones you should be able to hold in right orientation.

https://youtu.be/AP_10I7anvk

20200306_134256.jpeg
 
Last edited:
Hi Emerson,

soryy but I can't get (my bad english) WHEN the little red crocodile lead got destroyed. What were you attempting at that moment ? Seems to me that the lead somehow made contact with the body, shorting it to ground. I=U/R : little R = VERY high I = wire destroyed ...

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)
 
Bernievarian said:
Hi Emerson,

soryy but I can't get (my bad english) WHEN the little red crocodile lead got destroyed. What were you attempting at that moment ? Seems to me that the lead somehow made contact with the body, shorting it to ground. I=U/R : little R = VERY high I = wire destroyed ...

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)
Click to expand...

Hey berne.

No my fault, it was something i remembered last minute in the video and probably rushed through it.

but what happened was.

1) I connected my multi meter via crocodile clips to the positive and negative bolts on the battery terminal posts (ready to do a load test)

2) Because i am on my own, i then put the body / screen of the multi meter on my windscreen so i could see the volts change as i turn on things inside my car.

3) As i turned on my headlights and then blower motor to max i noticed smoking and simply turned everything off in a bit of a panic. Then when i went back to the engine bay and I saw the red crocodile wire completely melted.

It could be true what you say may have happened as I was not watching inside the engine to see if the wires moved and touched anything. I will probably need to do the test again with another person to see for sure so i can keep an eye out. But for sure there is something else going on, but feel I have done everything I know but my car keep passing the checks but how she acts is a different story?
 
So current update: I have replaced the battery as.my battert tester (topdon arti101) sad it was bad and it was about 1.5 years over its recommended life.

1) Performed a cranking test 3 times : New Battery: 9.73v / 9.39v and 9.59v all advised as low by the battery tester.

2) Performed various load tests
- No load: 14.39v
-RPM at 2500 revs : 14.19v.
-Headligts / fog lights rear & front / blower max : 13.90v.
Headlights / fog lights rear & front / blower max / dome light: 13.23v.
Headlights / fog lights rear & front / blower max / dome light/ rear demister : 12.47v.

After doing the load test the results seem to show that there is definitely a drop in voltage or the alternator maybe damaged. As i believe with a fully loaded car it should read 13.5v or higher. The whine noise is still there that drops in tone should you turn things on and off and also the headlights still dim if you pull the window closed.

Can anyone tell me in regards to the low cranking values as i start my car, if this could be something else, as it cannot be the battery as it is brand new but i thought this test was assoicated with the battery's health?

Tomorrow i plan to jack up my car and do some alternator tests via youtube watching to now start ruling that out.




20200318_132313.jpeg20200318_132503.jpeg
 
Hi Emerson,

those figures seem quite normal to me.

Say a 450 CCA battery, its internal resistance would be R=U/I or 5,4/450=0,012 ohm.
Your cranking voltage drop being 2,87v, cranking I is U/R or 2,87/0,012= 240 amps.

So why 5,4 volts for internal resistance math ?
CCA is the max current that a full charged battery (12,6V) can deliver during 30sec while remaining at 7,2V ... and 12,6 - 7,2 = 5,4

Same rule applies to other consumers: (next math "rounded" at 12V)
- 2x60W bulbs=120W=10A, ΔU = 10 x 0,012 = 0,12 V
- 240W demister=20A, Δ = 20 x 0,012 = 0,24 V

As you can see, the voltage drop will be proportionnal with the battery "size" (ability to deliver current) and its internal resistance. Also as soon as you increase, even slightly, the current path resistance, the voltage drop will drammatically increase !

In your case, the whining noise shows the alternator tries to compensate those voltage drops (its aim is to reach 14V-ish) but for some reason can't.

I'd have a close look at the alternator connections first, then if they ARE (not only seem) ok, the inductor coil brushes would be my next investigation...

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)

- cranking U drop: 12,6-9,73=2,87v
 
Bernievarian said:
Hi Emerson,

those figures seem quite normal to me.

Say a 450 CCA battery, its internal resistance would be R=U/I or 5,4/450=0,012 ohm.
Your cranking voltage drop being 2,87v, cranking I is U/R or 2,87/0,012= 240 amps.

So why 5,4 volts for internal resistance math ?
CCA is the max current that a full charged battery (12,6V) can deliver during 30sec while remaining at 7,2V ... and 12,6 - 7,2 = 5,4

Same rule applies to other consumers: (next math "rounded" at 12V)
- 2x60W bulbs=120W=10A, ΔU = 10 x 0,012 = 0,12 V
- 240W demister=20A, Δ = 20 x 0,012 = 0,24 V

As you can see, the voltage drop will be proportionnal with the battery "size" (ability to deliver current) and its internal resistance. Also as soon as you increase, even slightly, the current path resistance, the voltage drop will drammatically increase !

In your case, the whining noise shows the alternator tries to compensate those voltage drops (its aim is to reach 14V-ish) but for some reason can't.

I'd have a close look at the alternator connections first, then if they ARE (not only seem) ok, the inductor coil brushes would be my next investigation...

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)

- cranking U drop: 12,6-9,73=2,87v
Click to expand...
Thanks berne this is definitely my weak side of my.mechanical game. I am trying to learn the basics and add this to skill set. I will check connections tomorrow and report back. Weather stopped.me.today.
 
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