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so got in my car to go run a few errands and it started fine... got to my first stop picked up a few things and went out to the car and it was dead a rock...so I'm like WTF... get out my power pack I keep in trunk, hook it up and nothing... not even a click... Call my wife to come for a jump and same thing... Again i'm like wtf...figure it might be a dead cell or shorted cell... I call Hagerty for a flatbed to the dealer and they just F*$K up so bad with the wrong tow companies I send my wife back home for my tools... She comes back and I take the terminals off the battery and put them back on and the car starts right up!!! Now there really wasn't any corrosion on the posts at all so I'm at a bit of a loss on what transpired... Service manager from dealer calls me and tells me to bring it in... They look at it and the only thing they're thinking is the battery under load was marginal even tho i always keep it on a tender or that the + cable is suspect... they did not put it on a lift to see how the connection at the starter was tho... So at this point they want to replace the battery cables which i'm not totally against... They said the also measured the resistance of the + cable and it was at .3 ohms which would've dropped my voltage possible enough to not start the car... The battery voltage when I measured it at the battery was 12.1v so effectively dropping it 11.8v which I know is not a good thing... I know I probably need a new battery (3.5 yrs old) but just looking at some thoughts on this...Thanks....
Whoever at this dealership did a “resistance” check of your battery B+ cable is an IDIOT !!…you can have all but a few strands of that cable missing and still read 0.3 ohms…the current has to be carried to the starter and all of that current back to the battery on the ground circuit…if the car is still there tell them to do a voltage drop check of the cables…that is the correct and only way to check….after the battery is load checked do you proceed to the voltage drop check…tell them to watch this video and educate themselves…find an auto electric shop in your area !!…if you have the car now you can take a jumper cable and connect it from battery negative to a clean spot on the engine block…you are giving the ground circuit an alternate path back to the battery…if you have a 12 volt test light connect it to battery negative and while starting the car probe a clean spot on the engine block..the test light should NOT illuminate…if it does the battery negative circuit is faulty…may be the battery negative block ground…I believe your GS battery is in the trunk so testing is a little more involved…don’t know if you have a manual or not ??
GS battery is in the engine compartment.. so I did have some voltage tho as the radio reset itself and had 12.1v at the battery, just nothing happened when i tried to start the car... taking the terminals off and putting them back on resolved the problem tho... that's what I don't understand... if there was something wonky in the starting circuit I would think removing and replacing the terminal wouldn't fix that...great video tho... thanks...
GS battery is in the engine compartment.. thanks tho
Well if you are unfamiliar with electrical testing find an auto electric shop…where in central Florida are you located ??..a fully charged lead acid battery is 12.66…AGM is 12.80 !!
Well if you are unfamiliar with electrical testing find an auto electric shop…where in central Florida are you located ??..a fully charged lead acid battery is 12.66…AGM is 12.80 !!
so my battery measured 12.1 at the posts when this happened... now it's 12.95 after being on the tender overnight... now one thing I neglected to mention is that the ignition switch had no results when I pushed it... I would think it should've went to acc or tried to start the car... nothing... so after watching the video a few times, IMHO i would think the relay isn't working and got reset when I took off the terminals??? thoughts...
12.1 is around 50% charged whether AGM or lead acid…get it charged or tested…when you put your foot on the brake or push the bottom of the starter button to enter “Acc” mode do you hear a series of “clicks”…so said the car is recently purchased so you may not know these little things…if you hold the bottom of the starter button down for about 5 seconds the green start button light will illuminate and the car will be in “run” or “ignition on” mode…is the car doing any of this ??…to rule out the starter and cables remove Crank Relay 43 underhood fuse box…get a paperclip and bend into a U…with car in neutral or park with E brake set jump 30 and 87…car should crank !!…if you have a test light unbend clip and place in terminal 86…a test light probe may be too thick and damage the terminal…when you try to start the car test light should illuminate or if you have a DVOM you should see 12 volts there…any “no fob detected” messages ??…try placing FOB in back up antenna slot and see if car starts...and BTW a dealership shouldn't "THINK" the battery is marginal...they should KNOW !!
so when I pressed the start button, nothing happened... no green light no yellow for acc, nutin... I'm the original owner and batteries have never lasted me more then 4 yrs... no FOB messages at all just actually replaced that battery last week... dealer did a load test on the battery and said it was marginal... i'm gonna get a new battery but to be honest I don't see this as an issue even tho it was only 12.1v at the posts... I would think it would have at least tried to crank... also since I removed/replace the battery terminals the car is fine... go figure...
If your charging system is good it should be charging your battery and when you shut down the battery voltage should NOT be 12.1…you using an AGM or lead acid…when I bought my C6 a few years ago it had a Yellow Top that was 6 months old…I removed it and got an AC Delco Professional lead acid…AGM’s are just too hard to maintain if they are discharged..batteries in Florida on last 4 years at best because of the heat….Everstart batteries at Walmart have been highly rated on Consumer Reports for years…if your car came with a lead acid battery from the factory you don’t put in an AGM…the ECM charging strategy is based on the lead acid battery it came with !!…if you get a new battery we can do a charging system voltage drop test with your multimeter…only take a few minutes…make sure your FOB new battery is around 3.2 volts…don’t assume it is a fresh battery.
ya I have a duralast gold lead acid battery... because it gets around 110* in the garage in the summer I actually put AC in my garage... hehe I'll be buying the battery tomorrow so let me know how to do the charging circuit voltage drop test... BTW the car is bone stock except for a mild to wild switch... I also took out the onstar fuse... Thanks again for your help... if you a bit closer i'd drive it over...
Yeah, it’s pretty hot in my garage too in the summer and I was thinking of putting in a ductless mini split…for those of us living in Florida battery CCA isn’t important…RC (Reserve Capacity) in much more important …if you can get 110 or 120 minutes the better…my 08 only draws 620 amps for a split second (inrush current) just to get the motor turning and then 150 AMPS after that if it were to continue to crank…putting in a 1000 CCA battery isn’t going to make the car start any stronger…when you get the battery make sure it’s fully charged as it may have been sitting on the shelf for awhile….do you have those crummy OEM battery terminals ??…if so get rid of them and go to Autozone and get the gold plated or so they say ones.
To do the charging system voltage drop check run the engine at 2500 RPM and if you don’t have a scan tool to set the RPM a 2x4 wedged from your seat to the gas pedal can do that…put some loads on the electrical system such as high beams, AC, blower on high, seat heaters…place DVOM on a low voltage setting because you shouldn’t see more than a 0.5 volt drop on positive or negative side…place positive lead of meter on the alternator B+ and the other lead on battery B+….shouldn’t be more than 0.5 volt…now place black lead of meter on the alternator case and red lead on battery negative…still no more than 0.5…I will post of picture of my reading below…I would also make sure you don’t have a parasitic draw on the battery when the car sits…disconnect the negative terminal and place meter on amp setting and place meter leads in between (in series) the disconnected cable and battery terminal…max current draws depends on the RC of the battery…use RC divided by 4…100 minute RC is 25 milliamp max…it may take 15-20 minutes for the cars modules to go “to sleep”…you will see it slowly decrease.
ok.. I'll check that out... I bought a minisplit daizuki unit for my garage... works great... did you solder the ends of the cable before you put them in the new terminals?
ok.. I'll check that out... I bought a minisplit daizuki unit for my garage... works great... did you solder the ends of the cable before you put them in the new terminals?
Yes, I put some solder inside the ends and then tightened them up...they won't come out !!
new battery in and charging circuit test ok... Haven't done terminals yet as I need to find a good solder iron for that size cable.. will do a parasitic check this week, but don't think that's the issue... old battery looked to be bulging a bit on the sides...
new battery in and charging circuit test ok... Haven't done terminals yet as I need to find a good solder iron for that size cable.. will do a parasitic check this week, but don't think that's the issue... old battery looked to be bulging a bit on the sides...
Great....as far as the drain just record the battery voltage and then overnight check it again and see how much it drops....which battery ??
After I installed mine I found the same ones on Amazon but with the plastic covers…the covers fit perfect and now I have 2 extra terminals…around $15.00 !!
ill give you the data ive collected over the years on mine concerning batteries and no starts
1. my car starts on 12.1 volts with ease. yes thats a little low. most idle batteries hover in the 12.5-12.6 range. batteries get blamed for a ton of things on these cars, some accurate and some not. i bought a gooloo booster. it will start my 7.3 diesel so if it wont start my vette its not a volatage issue. dont ignore the battery, always wise to check, but dont let people convince you to keep checking and changing it if you have already ruled it out.
2. it sounds like your doors opened. i presume they were locked. if so then you RCDLR and BCM are talking and see your FOB. thats a very good thing.
3. When it does it again, check to see if you can get in acc mode. just hit the start button no feet on pedals. if no then very good chance the button is acting up. if acc come one then you know the car sees the button but its the starting circuit
3. if the acc mode is working you may want to investigate how to check you clutch pedal sensor or brake pedal sensor it auto. this safety interlock could be holding you out.
what concerns me is pulling the cable off "fixed" it. that is usually a sign of the more difficult problems.
Also, my 2005 M6 will sit for 3 weeks and the battery is good enough. four weeks and im usually going to have to jump it off. i have read many post that say these cars will pull a battery down in under a week. that is nonsense. the tenth of an amp these cars pull while off will not brick a battery in a week. the battery being old and weak yes, but on a healthy car and battery no.
i am just going on about the battery advice because i have seen so many people give bad advice. replace the battery, replace it again, replace the FOB battery, replace it again. replace it again. batteries do cause trouble and FOB batterys do cause trouble but replacing them out of desperation is not trouble shooting, its just wasting money.
one final piece, this drove me nuts for a few weeks. i kept my FOB in my pocket. i am always around the cars. at times buttons were getting pushed in pocket and waking up the car. then i would find the car dead after a day or two. these cars will hammer a battery if they are not all the way off and kept off. when my car wakes up it pulls 0.35 amps if i recall. i stopped carrying my FOB. and my this headache stopped. dont think this is what is going on with yours, but its more just a headups if these cars wake up and you dont know it the battery will be pulled down quickly.
ill give you the data ive collected over the years on mine concerning batteries and no starts
1. my car starts on 12.1 volts with ease. yes thats a little low. most idle batteries hover in the 12.5-12.6 range. batteries get blamed for a ton of things on these cars, some accurate and some not. i bought a gooloo booster. it will start my 7.3 diesel so if it wont start my vette its not a volatage issue. dont ignore the battery, always wise to check, but dont let people convince you to keep checking and changing it if you have already ruled it out.
2. it sounds like your doors opened. i presume they were locked. if so then you RCDLR and BCM are talking and see your FOB. thats a very good thing.
3. When it does it again, check to see if you can get in acc mode. just hit the start button no feet on pedals. if no then very good chance the button is acting up. if acc come one then you know the car sees the button but its the starting circuit
3. if the acc mode is working you may want to investigate how to check you clutch pedal sensor or brake pedal sensor it auto. this safety interlock could be holding you out.
what concerns me is pulling the cable off "fixed" it. that is usually a sign of the more difficult problems.
Also, my 2005 M6 will sit for 3 weeks and the battery is good enough. four weeks and im usually going to have to jump it off. i have read many post that say these cars will pull a battery down in under a week. that is nonsense. the tenth of an amp these cars pull while off will not brick a battery in a week. the battery being old and weak yes, but on a healthy car and battery no.
i am just going on about the battery advice because i have seen so many people give bad advice. replace the battery, replace it again, replace the FOB battery, replace it again. replace it again. batteries do cause trouble and FOB batterys do cause trouble but replacing them out of desperation is not trouble shooting, its just wasting money.
one final piece, this drove me nuts for a few weeks. i kept my FOB in my pocket. i am always around the cars. at times buttons were getting pushed in pocket and waking up the car. then i would find the car dead after a day or two. these cars will hammer a battery if they are not all the way off and kept off. when my car wakes up it pulls 0.35 amps if i recall. i stopped carrying my FOB. and my this headache stopped. dont think this is what is going on with yours, but its more just a headups if these cars wake up and you dont know it the battery will be pulled down quickly.
Thanks I appreciate your assistance... my concern also that just removing/replacing the battery terminals woke the car up...
After I installed mine I found the same ones on Amazon but with the plastic covers…the covers fit perfect and now I have 2 extra terminals…around $15.00 !!
ya, I was looking at those also... my concern is getting the old terminal ends off without getting bits of wire all over the damn place... Also getting some solder on wire is gonna be tough.. I don't have a torch or my old soldering iron to melt some solder on the cable...
another c6 not starting issue...
