Another 12V problem

[Suntory1980]

Background:

New battery 4 months old.

2 cold nights in the UK and my battery is playing up

I got this reader:
http://image.made-in-china.com/2f0j0...-XL-Car-V-.jpg

Car starts well,radio on with subwoofer, then within 5 min at traffic lights car stalls I read the car battery tester and its jumping from 12V-11.9V I luckily manage to start again.

I drive off and immediately turn on the headlights, the reader jumps from 12.0V to 13.9V-14.0V driving it with caution and heater on for 10 minutes and I switch off the headlights.

now the voltage is hoovering from the range 12.4/.5V-12.0V , i try to floor it but I have no clue when the DC converter kicks in and tries to charge the battery. I have never seen my car battery fully charged as in a steady reading of 12.7V or above

(info:How to Tell if a 12V Battery Is Charged | eHow.com)

whats going on here, I need to go to work tomorrow with the car.

Bad ground straps? where are they all situated?


Why is the DC converter not kicking in?(It kicks in when the headlights are on.)
I found on another thread it kicks in when its BELOW 12V????

Suppose my car stalls with a minimum current of 12V isn't that abit risky???
LINK:12v Battery vs Alternator issue

What is the average battery reading of a good battery in an Insight? I found out that its around 12V
link:How critical is the DC/DC converter?

But that contradicts that a healthy battery is at 12.7V or above statement


Any help is appreciated.

Edit: found the ground straps locations
Ground locations

FYI ground straps are just fine

[retepsnikrep]

Your battery voltages sound normal to me. The insight is a bit notorious in not really keeping it well charged, IMHO the dc-dc converter output is too low when lights are off at ~12.5v it should be nearer 13.8 or so. Try charging the battery with a standalone 12v charger. See if the problem re-occurs. I assume there are no fault codes nor warning lights illuminated.

[Suntory1980]

Originally Posted by retepsnikrep

Your battery voltages sound normal to me. The insight is a bit notorious in not really keeping it well charged, IMHO the dc-dc converter output is too low when lights are off at ~12.5v it should be nearer 13.8 or so. Try charging the battery with a standalone 12v charger. See if the problem re-occurs. I assume there are no fault codes nor warning lights illuminated.

Peter,

The DC-DC converter does go to 13.8V with the lights of, but it doesn't hold it for a long time....then it drops to 12.0-12.5 range....its like pure random how the DC converter kicks in.....


with this cold weather I am more worried that it wont start on a cold winter morning....

[retepsnikrep]

The dc-dc is controlled by the ecm which in turn monitors the eld (electronic load detector). It's just not great in the insight, so charge you battery as i suggested and see how you get on. Take some jump leads with you. Lots of short journeys are punishing for the battery especially if you have some huge drain on it from your sub amp or whatever. How do you have your sub amp wired if it is direct to the battery posts then you will be bypassing the eld which then can't compensate for the extra load.

[Suntory1980]

Originally Posted by retepsnikrep

The dc-dc is controlled by the ecm which in turn monitors the eld (electronic load detector). It's just not great in the insight, so charge you battery as i suggested and see how you get on. Take some jump leads with you. Lots of short journeys are punishing for the battery especially if you have some huge drain on it from your sub amp or whatever. How do you have your sub amp wired if it is direct to the battery posts then you will be bypassing the eld which then can't compensate for the extra load.

The amp is wired straight from the 12V battery through the firewall....and I do 20-30min commutes to work once a week......i am charging the 12V battery at the moment....is there a better way to hook up the amp?

[Cobb]

There are plenty of articles online about this issue and non hybrid Hondas. Otherwise drive with your lights on.


Sent from my Autoguide iPod touch app

[retepsnikrep]

Ha I suspected as much wired straight to the battery naughty boy!
How much does it draw. Try wiring through the radio + feed or 12v power socket if amps is OK.

[Eli]

When you see 12.xV on the battery, it means the DC-DC isn't currently operating. I don't know why it turns on and off like it does, but that's the reason for the system maintaining the 12V battery low in our cars. It isn't like an alternator that puts out ~14V anytime the engine is running.

[Suntory1980]

Originally Posted by Eli

When you see 12.xV on the battery, it means the DC-DC isn't currently operating. I don't know why it turns on and off like it does, but that's the reason for the system maintaining the 12V battery low in our cars. It isn't like an alternator that puts out ~14V anytime the engine is running.

Yeah peter abit naughty....well just a fictive scenario:
Damn cold day, your insight fires up...somehow u manage to stall before a traffic light when its in autostop.

My questions are:
*whats the "danger zone" (voltage range wise since i have a reader)that this car wont start? Today at 11.9v it was struggling
*does it means as long the battery LIGHT stays OFF, the car will restart at any stall?
*if the system maintaining th 12V low, how to keep it reasonably top up in cold days? Battery charger? It seems counterintuitive having a healthy battery and DC converter and manually top the Battery up...


OK i understand there are threads about the 12V battery however the solution running your lights on doesnt make me feel i am saving the world....are all UK owners running with jumpleads and starters in their car?

[aisbell]

I've been using only absorbent glass mat (AGM) batteries since my OEM battery failed just prior to its warranty period. I've used small Odyssey batteries and larger Mazda Miata batteries. One Miata battery lasted for 5 years, but its replacement could not be charged manually higher than 12.4 v. after only a year (12.8 v. is normal), so I replaced it with an Odyssey PC680 within the past year. When I removed it from my Insight in October in preparation for storing my car over the winter, its voltage was only 12.4 v. Fortunately, I was able to manually charge it to a steady-state voltage of 12.8.

I don't want to drive with my headlights on to force the DC-DC converter to charge my 12 v. battery, and I don't want to have to manually charge my 12 v. battery periodically (my Insight should do this correctly). Might it be possible to fool the DC-DC converter into maintaining a higher 12 v. battery charge level? Could the ELD signal be faked to a higher load level so that the DC-DC converter will charge the 12 v. battery more frequently?