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Thread ID: 124707	2012-05-14 08:52:00	Charging the car battery.	Nomad (952)	PC World Chat

Post ID	Timestamp	Content	User
1275305	2012-05-17 22:03:00	If you have a car battery with the green 'Charge-Eye' in it - it's really old. Very old. Have a retirement party for it and go out and buy a new one. I have a 1 year old batt with one of those :eek: What the reality with jumper leads blowing car computors ?? lots of old wives tales with that one Only reason I can think of is if the flat batt has gone open circuit (not very likely)	1101 (13337)
1275306	2012-05-17 22:11:00	[QUOTE=SurferJoe46;1093192] non-flammable gasolines we have here in the US. QUOTE] Non inflammable gas lol.	prefect (6291)
1275307	2012-05-17 22:29:00	There hasn't been a seeing-eye battery in the US since the late 1980s or so - so your having one now reeks of old stock being sold to foreigners. Sorry - but they were a bust here and there were quite a few lawsuits for them reporting green and the battery was technically dead. If you pay attention to the polarity - then there is no risk of smoking an ECM by jump starting or boost-charging a dead battery. These computers in recent cars are really very robust and can take a lot more voltage than the charging system can deliver, even if it fails particularly 'hotter' voltage-wise, than normal. I can honestly say that in 47+ years in the automotive repair field, that I've only had ONE dead ECM and that was from reasons that I could not define for sure. Suffice to say that it was also wrapped around a power pole and it might not have actually failed unless it got shocked to death by a lot of negative G's. If you aren't sure of the polarity, just look for 1) the larger battery post or 2) the dirtiest battery post or 3) the charge wire coming from the alternator (or the alternator's bus terminal) to the battery or 4) any signs, logos or statements that the POSITIVE post is the one you think it is. THEN attach the POSITIVE posts of both batteries together with the RED or + symbolized cable. Attach the NEGATIVE post of the dead/low battery with the BLACK or - symbolized jumper connector. DO NOT START the serving vehicle! IN fact, make sure that the ignition key is OFF too. This is important - but again, and I haven't seen any problem here, but it is somewhat documented as a POSSIBLE problem-maker ---> you do NOT want the engine of the vehicle with the good battery to be running since this will have the ECM energized and any NORMAL transient voltage spikes from the collapsing fields of the starter MAY cause an untoward situation to the running ECM. That is the ONLY situation that isn't regularly covered in 'Jump Starting Cars -- 1A' class! Now - let the batteries BOTH sync a little bit before you try the ignition on the dead vehicle. Take a few minutes. You might see that the headlights are on - or some accessory is still running on the dead vehicle and now's the time to turn everything off first before trying to start the dead vehicle. The reason for waiting is simple: most 'jumper cables' are not really good enough to start a vehicle all by themselves. They are -at best, just 'booster cables' and they cannot be trusted to carry the amperage that's required to actually crank an engine. I've seen them melt the alligator ends off - go on fire - if not just righteously smoke badly - from trying to carry a shorted battery AND the current demand for the starter at the same time. Take your time with that sync-time and keep your eyes open for smoke, sparks and other untoward actions. THAT'S the big reason for being careful. Oh yeah --- don't let the vehicles actually touch each other either. Chrome bumper-to-bumper contact can cause some interesting results that you may not be expecting. If I've confused you - or anyone - let me know.	SurferJoe46 (51)
1275308	2012-05-17 23:11:00	Hey Joe, I may have missed something. You mean the good battery car should not be started up? That they should both be both and let it sync and the weak battery car starts up. Last time when the roadside assist guy came over ... his truck's engine was running .....	Nomad (952)
1275309	2012-05-17 23:42:00	The reason for NOT having the engine running on the PROVIDER'S engine is to keep any and all spikes from the starter from getting into a good running ECM. Cranking mode and running mode are different on most ECMs, in that they have a very filtered bypass during cranking the engine time, and then once the engine is qualified as running (via the cam position sensor, the MAF or MAP or the B-Map sensor AND the TAC sensor, the ECM switches to an intermediate operating mode that awaits further green-board acquisition of the CTS (coolant) O2S (oxygen sensor), and a few other parameters depending on system - THEN the ECM goes into full closed mode. It is during the closed mode that it is susceptible to being hit by transients and the service guy in a truck wasn't too concerned about his ECM 'cause either he didn't have one, was too ignorant to realize that he has one - or the most likely is that he was in a hurry and didn't care if his truck had problems or not. If he's in business providing roadside assistance, then he's at risk, not you. It's always BEST to have the providing vehicle engine OFF. There's no sense in the risk to you or a Good Samaritan helper. Vehicle computers run on a purified and very clean 5VDC system, and they are not happy with being mistreated, even though like I said, they are very robust. Since it's YOUR turn at bat here needing help, it MAY be expensive to not consider a few nasty possible results. I'm just trying to help keep youse guys whole and well-monied. Oh - a closing statement: modern lead-calcium batteries do NOT recover from being discharged very well - if at all. Once they are below 9.5 Volts or so, they are suspect from that moment on and can spontaneously discharge since they like to eat themselves internally.	SurferJoe46 (51)
1275310	2012-05-18 00:30:00	There hasn't been a seeing-eye battery in the US since the late 1980s or so - so your having one now reeks of old stock being sold to foreigners. Sorry - but they were a bust here and there were quite a few lawsuits for them reporting green and the battery was technically dead. The US needs more people that understand that the magic eye is only in one of the cells and the others could be different and fewer lawyers. Whether it does any good or not the magic eye is available in new batteries in other markets including NZ.	PaulD (232)
1275311	2012-05-18 01:57:00	It's just a gimmick. There was a situation where a husband had to get his preggo wife to a delivery room, and knowing that his battery said it was good with it's stupid green eye, it failed when he went to start it, the baby was breach and died of suffocation during a complicated birth. That cost Delco a lot of money. The husband and wife were 160 miles from the nearest medical facility and paramedics didn't get to them in time. Some people in the US live so far away from medical facilities that it is feasible that this might be a justified situation. I remember on the cardboard sleeves in which fan belts are shipped, it says: "Turn off engine before attempting to change or adjust fan belts" --- because YOU KNOW some dork tried to do it with the engine running.	SurferJoe46 (51)
1275312	2012-05-18 04:51:00	A case like that in NZ would be thrown out in fact you wouldnt even find a lawyer that stupid to try and defend it.	prefect (6291)
1275313	2012-05-18 05:48:00	Hey Joe, I enjoyed reading all your wisdom on car batterys. :)	Trev (427)
1275314	2012-05-18 06:38:00	I didn't mention some of the tech that's being used to modulate charging rates by the ambient- compared to battery temperature- that the BCM monitors now too. Battery temperature is critical to certain charging rates, and if you were to hit a cold battery with very high charging rates, it could expand and swell the case and leak electrolyte. A hot battery will also liberate hydrogen faster, so the charging rate has to be dropped and allowed to float a bit more around full charge value, since it isn't working much if a vehicle is running at highway speeds. Modern vehicles use pulse modulation to charge the battery - a fairly new concept that keeps the battery charge rate to infinitely variable rates by turning ON and OFF the time of actual electron flow to and from the battery. Very interesting stuff. This is the advent of- and tech prep for- newer batteries and vehicular charging systems in the 40-100 VDC category. These new voltages are necessary for the no-camshaft engines of the future. The valves will be opened and closed by solenoids that are controlled by the ECM to change the cam profile and duration to correct AIR-FUEL ratios and keep performance high and emissions low. With no parasitic draw of horsepower operating a cam, timing gears, lifters, rockers, 'sticktion' and oil film viscosity factors of the oscillating and moving parts and the reciprocation of massive parts that need to accelerate and immediately decelerate and change direction of travel eg: the cam, lifters, springs, retainers, valves, etc - the effect will be to lower the lost power inside the design of the current type of engines. Then again, the cooling system will be digital motor driven as will be the AC/Heating system. If the world doesn't implode, automobiles are going to get very interesting soon. ECM = Emission Control Module (engine performance) BCM = Body control Module (preset comfort zones for cabin heating keyed off the RFI chip in the key fob for each individual driver, cooling, seat positions, personal phone lists, interior lights, interior radio/CD/MP3/Bluetooth, personal radio stations and volume, zone'd heating/cooling for passengers, etc) TCM = Transmission Control Module (self explanatory) ACM = Auxiliary Control Module (GPS, On-Star, Traction Control, ABS) CCM = Communications Control Module. (internal bus control firmware to keep data flow current and parity test itself constantly - @400GHz. Also the CCM reports to the mysterious 'Black Box' that the GVT wants to use to keep it's eye on you. Also for insurance-finance and police authorities to make sure vehicle is registered and insured IF it's being driven and if not, where it's parked so it can be impounded. There MAY be an alcohol/drug sniffer built into this too in the future.	SurferJoe46 (51)
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