Sort of a mechanical challange

[dolluper]

OK guess l sorted this out took awhile. Must admit learning still with this new tech on autos. OK here it is guy's a 2012 chevy impala 3.6 has a dead battery only on some mornings or after long drives. First l check charging system charges fine , batterry was 12.6 before charging system test. Also load test on battery was excellent . Do a Paris tic draw test on complete electrical system all checks out perfect no draw on the battery. Next grounds all checked perfect. What could cause this ghostly problem??

 

[dolluper]

Hint 23.00 bones Canadian fixed it

 

[alldodge]

Right now not a clue. So far our 12 Caddy has not had the issue, but my sister in law has a Hummer and if it is not driven for 3 days the bat is dead

 

[robert graham]

My experience is that a battery is capable of acting in strange ways....usually I just buy a new battery and the ghosts all go away.....

 

[bigdee]

My experience is that a battery is capable of acting in strange ways....usually I just buy a new battery and the ghosts all go away.....

x2.....intermittent batteries can check fine on load test!!

 

[jakedaawg]

Battery operated cooling fan coming on?

 

[bigdee]

Bad battery with shorted cell will drain down

 

[dwco5051]

Battery operated cooling fan coming on?

I think you might be the winner. A engine temp sensor is about $18 USD.

 

[dolluper]

OK guy's your close but no cigar. The car has started perfect since the fix for the last 2 weeks, through very cold days also.l had to examine wiring diagrams to figure it out. What l found was gm put a battery sensor which controls charging as it senses voltage in and out,it can also cause a no start condition when faulty. This is hard to believe but true. There really is no way to test it so l took a chance and replaced it. It's done the trick all is well for now. Apparently some foreign car makes have systems similar but incorporate it with a couple of fuses instead of a sensor. Happy wrenching guy's hope this helps you some day

 

[bigdee]

OK guy's your close but no cigar. The car has started perfect since the fix for the last 2 weeks, through very cold days also.l had to examine wiring diagrams to figure it out. What l found was gm put a battery sensor which controls charging as it senses voltage in and out,it can also cause a no start condition when faulty. This is hard to believe but true. There really is no way to test it so l took a chance and replaced it. It's done the trick all is well for now. Apparently some foreign car makes have systems similar but incorporate it with a couple of fuses instead of a sensor. Happy wrenching guy's hope this helps you some day

Some cars have a temperature sensor to detect if battery is being overcharged. It turns off charge until battery cools down. If this was the case your partially discharged battery should have failed the load test.

 

[alldodge]

What l found was gm put a battery sensor which controls charging as it senses voltage in and out,it can also cause a no start condition when faulty

Where is the sensor located and do you know the part number?

 

[dolluper]

It's on the negative battery cable close to the negative post on the impala chucked the box . Don't have part ..number may vary per vehicle

 

[dolluper]

Your in luck found box ac Delco
13505369 lts a BATTERY CURRENT SENSOR not a battery temperature sensor lf you have a tech 2 or equal you can test it that's why l said it was basically un testable .

 

[dolluper]

If it loses comunication with the ECM it will default to 13.8 volts and throw code U1016 or if it loses comunication with the BCM it will throw code U1064

 

[alldodge]

Your in luck found box ac Delco
13505369

Cool thanks :thumb:

 

[dolluper]

Great article here guy's to understand thsee newer systems
http://www.searchautoparts.com/motorage/technicians/underhood-service-repair/staying-charge

 

[dwco5051]

Thank you for sharing that website. Since my first car had an opening through the grill to insert a crank to hand start it, a 6v system, a generator, and an adjustable voltage regulator I sometimes think the world is passing me by. I learned something today.

 

[dolluper]

That's wat this iboats site is for knowledge and it has lots. Right now l'm working on a hack for this system . I think that it could be as simple as snipping the wire going to the ECM it should default to 13.8 volt charging full time but with battery charge light on have to play with some resistors to turn that off unless someone else already knows. Let us all know if you do

 

[bigdee]

Thank you for sharing that website. Since my first car had an opening through the grill to insert a crank to hand start it, a 6v system, a generator, and an adjustable voltage regulator I sometimes think the world is passing me by. I learned something today.

Amen brother. The days of carrying a few tools and a roll of duct tape are long gone. Now it is roadside insurance and a fat wallet!

 

[GA_Boater]

I disagree. Duct tape is still needed to hold the plastic bumper covers on. :doh: Give me the old chrome bumpers that bump like bumpers are meant to do!