Posted: 9/2/2009 1:54:31 PM EDT
|
I know, life threatening crisis, but it is for the woman.
Short version: My buddy is in Seattle on business. His wife is flipping because the car won't start. I'm getting ready to head out to take a look at it. Late model Honda minivan. Can I just swap in a new battery or are there stupid circuits to deal with? Also, what's the best way to check output from the generator on that kind of rig? Details would be helpful. I do some work on my own cars but they are older US models. What's your advice for this? |
|
Quoted:
Most auto parts stores will check the alternator and battery for free. Jump start the minivan, go there and proceed according to what they find. Otherwise, if you can't start it, change out the battery, then head to the auto parts store. If you jumpstart it with a bad battery, it wont run for very long at all, not even a few minutes. The Computer needs a set voltage to signal things like injectors and coils to operate. If the voltage isnt there, it aint gonna run. Not sure on where the battery is placed on a newer Honda mini-van, but be prepared to get the wrenches out along with the owners manual to find it. |
|
All you need to do is this;
1) Have someone jump the car. 2) Disconnect the battery. 3) If it stays running, replace the battery, be on your way. 4) If it dies right away, replace the alternator. If you have to replace the alternator, it is possible in an over-charge situation to wreck the battery...not usually the case, but it can happen. |
|
Quoted: All you need to do is this; 1) Have someone jump the car. 2) Disconnect the battery. 3) If it stays running, replace the battery, be on your way. 4) If it dies right away, replace the alternator. If you have to replace the alternator, it is possible in an over-charge situation to wreck the battery...not usually the case, but it can happen. NEVER do that. Ever. Check voltage before starting and after. If under 12 off, battery is discharged and could be defective. If under 13.2 running, alternator is weak or battery is shorted. If also spewing electrolyte yet voltage under 13.2, battery is defective with a short. If over 14.5 running, regulator is going full scale, check wiring to alternator (little wire to alternator, ignition on, engine off and disconnected, should be 5-9 volts.) |
|
Quoted: Most cars dont work this way anymore. It might certainly stay running if you disconnect the battery but more than likely you'll get service engine soon codes and lights on the dash. They will clear out later but your gonna wonder how they got there. All you need to do is this; 1) Have someone jump the car. 2) Disconnect the battery. 3) If it stays running, replace the battery, be on your way. 4) If it dies right away, replace the alternator. If you have to replace the alternator, it is possible in an over-charge situation to wreck the battery...not usually the case, but it can happen. Harbor freight sells a cheap battery load tester for about 15 bucks. for a one time use its probably worth it. |
|
Quoted:
Quoted:
All you need to do is this; 1) Have someone jump the car. 2) Disconnect the battery. 3) If it stays running, replace the battery, be on your way. 4) If it dies right away, replace the alternator. If you have to replace the alternator, it is possible in an over-charge situation to wreck the battery...not usually the case, but it can happen. NEVER do that. Ever. Check voltage before starting and after. If under 12 off, battery is discharged and could be defective. If under 13.2 running, alternator is weak or battery is shorted. If also spewing electrolyte yet voltage under 13.2, battery is defective with a short. If over 14.5 running, regulator is going full scale, check wiring to alternator (little wire to alternator, ignition on, engine off and disconnected, should be 5-9 volts.) There you have it. You can completely diagnose with a good voltmeter. ETA - I'll add if you get a new battery, make sure the pos. and neg. posts are on the correct sides for that vehicle. For example, my truck takes a group 24 battery, but it needs a group 24-F, which is reverse pos and neg posts. Or else the battery cables won't reach. |
|
Quoted:
ETA - I'll add if you get a new battery, make sure the pos. and neg. posts are on the correct sides for that vehicle. For example, my truck takes a group 24 battery, but it needs a group 24-F, which is reverse pos and neg posts. Or else the battery cables won't reach. Not an issue if you go to a bona fide auto parts place and tell them "I need a battery for an XX YYYYYY ZZZZZZZ" |
|
Quoted:
Quoted:
ETA - I'll add if you get a new battery, make sure the pos. and neg. posts are on the correct sides for that vehicle. For example, my truck takes a group 24 battery, but it needs a group 24-F, which is reverse pos and neg posts. Or else the battery cables won't reach. Not an issue if you go to a bona fide auto parts place and tell them "I need a battery for an XX YYYYYY ZZZZZZZ" I know, but you never know. It could save some headache. |
|
Quoted:
All you need to do is this; 1) Have someone jump the car. 2) Disconnect the battery. 3) If it stays running, replace the battery, be on your way. 4) If it dies right away, replace the alternator. If you have to replace the alternator, it is possible in an over-charge situation to wreck the battery...not usually the case, but it can happen. Please don't do that on a modern computer controlled vehicle. |
|
Quoted:
All you need to do is this; 1) Have someone jump the car. 2) Disconnect the battery. 3) If it stays running, replace the battery, be on your way. 4) If it dies right away, replace the alternator. If you have to replace the alternator, it is possible in an over-charge situation to wreck the battery...not usually the case, but it can happen. That was real good advice............in 1967. |
|
Quoted:
Quoted:
Most auto parts stores will check the alternator and battery for free. Jump start the minivan, go there and proceed according to what they find. Otherwise, if you can't start it, change out the battery, then head to the auto parts store. If you jumpstart it with a bad battery, it wont run for very long at all, not even a few minutes. The Computer needs a set voltage to signal things like injectors and coils to operate. If the voltage isnt there, it aint gonna run. Not sure on where the battery is placed on a newer Honda mini-van, but be prepared to get the wrenches out along with the owners manual to find it. That is complete and utter bull shit. I've run many OBD1 and OBD2 Honda's on nothing but the alternator..Alot of race cars do this to drop 20-30 lbs instantly..start the car with a jumper pack and make sure you don't shut it off. you can jump the existing battery or even take off the battery terminals and hook them directly to the jumper cables, start the car, unhook the jumpers and if the alternator is good..the car will run fine..until you shut it off and it needs to start again. And thats one way to field test an alternator. Get the vehicle started and un hook the battery..if the idle drops drastically or the engine stalls..the alternator is bad or is on the way out. The preferred way is to test the terminals on the battery (or without them on the battery) with a voltmeter. anything above 13 volts with the engine running will work. And alot of people will armchair that this won't work or its a bad idea on a NEW car, which it probably is..but i've done it..many-a-time. One main reason to back that up is the power wire running from the alternator runs DIRECTLY to the positive cable coming off the battery..with more voltage than battery has. If the car is running, It won't make a difference if there is a battery there or not..until you shut it off. |
|
Quoted:
Quoted:
Quoted:
Most auto parts stores will check the alternator and battery for free. Jump start the minivan, go there and proceed according to what they find. Otherwise, if you can't start it, change out the battery, then head to the auto parts store. If you jumpstart it with a bad battery, it wont run for very long at all, not even a few minutes. The Computer needs a set voltage to signal things like injectors and coils to operate. If the voltage isnt there, it aint gonna run. Not sure on where the battery is placed on a newer Honda mini-van, but be prepared to get the wrenches out along with the owners manual to find it. That is complete and utter bull shit. I've run many OBD1 and OBD2 Honda's on nothing but the alternator..Alot of race cars do this to drop 20-30 lbs instantly..start the car with a jumper pack and make sure you don't shut it off. you can jump the existing battery or even take off the battery terminals and hook them directly to the jumper cables, start the car, unhook the jumpers and if the alternator is good..the car will run fine..until you shut it off and it needs to start again. And thats one way to field test an alternator. Get the vehicle started and un hook the battery..if the idle drops drastically or the engine stalls..the alternator is bad or is on the way out. The preferred way is to test the terminals on the battery (or without them on the battery) with a voltmeter. anything above 13 volts with the engine running will work. And alot of people will armchair that this won't work or its a bad idea on a NEW car, which it probably is..but i've done it..many-a-time. One main reason to back that up is the power wire running from the alternator runs DIRECTLY to the positive cable coming off the battery..with more voltage than battery has. If the car is running, It won't make a difference if there is a battery there or not..until you shut it off. Some vehicles have strategy built in to where the PCM will not command the alternator to charge if the static battery voltage is below "X" amount. This is because trying to charge a discharged battery with an alternator is very, very hard on the alternator; alternators are not designed to charge dead batteries. Of course, you're the one advocating pulling battery cables while the engine is running. With all due respect, I don't think you have the right to call bullshit on anyone with that asinine recommendation. |
|
Quoted:
Quoted:
All you need to do is this; 1) Have someone jump the car. 2) Disconnect the battery. 3) If it stays running, replace the battery, be on your way. 4) If it dies right away, replace the alternator. If you have to replace the alternator, it is possible in an over-charge situation to wreck the battery...not usually the case, but it can happen. That was real good advice............in 1967. It was real good advice up until 1974 or so... 
Batteries die all the time. Having a situation where a battery dies instantly (loss of current flow within the battery when a cell goes bad for example) happens all the time. This is NOTHING different than disconnecting it while running. It will not hurt anything. Look at it this way: Because batteries CAN and DO sometimes go bad this way, it would be like a "ticking time bomb" in a car if the ECM in a car was susceptible to being fried because of it. It still works on modern cars, and in 20 years of wrenching, I have never had a problem doing it. Maybe I'm just lucky? |
|
The battery still acts as sort of an electrical buffer or sponge in the event of a failure.
Sure, it may work, it may not. It isn't wise IMO to universally say "Yeah, you'll be fine to test your alternator by disconnecting the battery cables while the engine is running." |
|
Quoted:
Quoted:
Quoted:
All you need to do is this; 1) Have someone jump the car. 2) Disconnect the battery. 3) If it stays running, replace the battery, be on your way. 4) If it dies right away, replace the alternator. If you have to replace the alternator, it is possible in an over-charge situation to wreck the battery...not usually the case, but it can happen. That was real good advice............in 1967. It was real good advice up until 1974 or so...
Batteries die all the time. Having a situation where a battery dies instantly (loss of current flow within the battery when a cell goes bad for example) happens all the time. This is NOTHING different than disconnecting it while running. It will not hurt anything. Look at it this way: Because batteries CAN and DO sometimes go bad this way, it would be like a "ticking time bomb" in a car if the ECM in a car was susceptible to being fried because of it. It still works on modern cars, and in 20 years of wrenching, I have never had a problem doing it. Maybe I'm just lucky? I had a 95 f150, the battery corroded internally. I would drive down the road hit a bump and the motor would die, would go thump the battery, and it would work till the next bump. Luckily it was a short drive home some back roads. That truck still has the original alternator. |
|
Quoted:
The battery still acts as sort of an electrical buffer or sponge in the event of a failure. Sure, it may work, it may not. It isn't wise IMO to universally say "Yeah, you'll be fine to test your alternator by disconnecting the battery cables while the engine is running." also not a good example. where does an alternator get its excitation voltage from? the battery, and if the load varies, it may not be able to keep it self excited. yes, some alternators are self exciting so thats a different can of worms. |
|
Quoted:
Quoted:
Quoted:
Quoted:
Most auto parts stores will check the alternator and battery for free. Jump start the minivan, go there and proceed according to what they find. Otherwise, if you can't start it, change out the battery, then head to the auto parts store. If you jumpstart it with a bad battery, it wont run for very long at all, not even a few minutes. The Computer needs a set voltage to signal things like injectors and coils to operate. If the voltage isnt there, it aint gonna run. Not sure on where the battery is placed on a newer Honda mini-van, but be prepared to get the wrenches out along with the owners manual to find it. That is complete and utter bull shit. I've run many OBD1 and OBD2 Honda's on nothing but the alternator..Alot of race cars do this to drop 20-30 lbs instantly..start the car with a jumper pack and make sure you don't shut it off. you can jump the existing battery or even take off the battery terminals and hook them directly to the jumper cables, start the car, unhook the jumpers and if the alternator is good..the car will run fine..until you shut it off and it needs to start again. And thats one way to field test an alternator. Get the vehicle started and un hook the battery..if the idle drops drastically or the engine stalls..the alternator is bad or is on the way out. The preferred way is to test the terminals on the battery (or without them on the battery) with a voltmeter. anything above 13 volts with the engine running will work. And alot of people will armchair that this won't work or its a bad idea on a NEW car, which it probably is..but i've done it..many-a-time. One main reason to back that up is the power wire running from the alternator runs DIRECTLY to the positive cable coming off the battery..with more voltage than battery has. If the car is running, It won't make a difference if there is a battery there or not..until you shut it off. Some vehicles have strategy built in to where the PCM will not command the alternator to charge if the static battery voltage is below "X" amount. This is because trying to charge a discharged battery with an alternator is very, very hard on the alternator; alternators are not designed to charge dead batteries. Of course, you're the one advocating pulling battery cables while the engine is running. With all due respect, I don't think you have the right to call bullshit on anyone with that asinine recommendation. I know, I must have been hallucinating working on all those Honda's. Honda's have an ELD or electronic load detector. It adjusts the field strength in the alternator(Also adjusts the idle up and down when you are playing with things like AC and the radio) depending on what the current draw is coming off from the battery. But they have a fail safe if the main battery fuse blows, it won't kill the car. which is why the ELD is after the main power cable(And after the alternator voltage input) in the fuse box on a Honda. It won't kill voltage coming from alternator. Only reduce it. What you are referring to is a crowbar circuit and there aren't that many vehicles out there with those, for the simple fact that it will leave you completely stranded if the battery dies, and you have to pop-start it. And if you read my whole post, you would have read that I said the "preffered way" which i should have said right way to check it would be to use a voltmeter on the battery. Just because a method is "old school" doesn't mean it doesn't work. |
|
Quoted:
Quoted:
Quoted:
Quoted:
Quoted:
Most auto parts stores will check the alternator and battery for free. Jump start the minivan, go there and proceed according to what they find. Otherwise, if you can't start it, change out the battery, then head to the auto parts store. If you jumpstart it with a bad battery, it wont run for very long at all, not even a few minutes. The Computer needs a set voltage to signal things like injectors and coils to operate. If the voltage isnt there, it aint gonna run. Not sure on where the battery is placed on a newer Honda mini-van, but be prepared to get the wrenches out along with the owners manual to find it. That is complete and utter bull shit. I've run many OBD1 and OBD2 Honda's on nothing but the alternator..Alot of race cars do this to drop 20-30 lbs instantly..start the car with a jumper pack and make sure you don't shut it off. you can jump the existing battery or even take off the battery terminals and hook them directly to the jumper cables, start the car, unhook the jumpers and if the alternator is good..the car will run fine..until you shut it off and it needs to start again. And thats one way to field test an alternator. Get the vehicle started and un hook the battery..if the idle drops drastically or the engine stalls..the alternator is bad or is on the way out. The preferred way is to test the terminals on the battery (or without them on the battery) with a voltmeter. anything above 13 volts with the engine running will work. And alot of people will armchair that this won't work or its a bad idea on a NEW car, which it probably is..but i've done it..many-a-time. One main reason to back that up is the power wire running from the alternator runs DIRECTLY to the positive cable coming off the battery..with more voltage than battery has. If the car is running, It won't make a difference if there is a battery there or not..until you shut it off. Some vehicles have strategy built in to where the PCM will not command the alternator to charge if the static battery voltage is below "X" amount. This is because trying to charge a discharged battery with an alternator is very, very hard on the alternator; alternators are not designed to charge dead batteries. Of course, you're the one advocating pulling battery cables while the engine is running. With all due respect, I don't think you have the right to call bullshit on anyone with that asinine recommendation. I know, I must have been hallucinating working on all those Honda's. Honda's have an ELD or electronic load detector. It adjusts the field strength in the alternator(Also adjusts the idle up and down when you are playing with things like AC and the radio) depending on what the current draw is coming off from the battery. But they have a fail safe if the main battery fuse blows, it won't kill the car. which is why the ELD is after the main power cable(And after the alternator voltage input) in the fuse box on a Honda. It won't kill voltage coming from alternator. Only reduce it. What you are referring to is a crowbar circuit and there aren't that many vehicles out there with those, for the simple fact that it will leave you completely stranded if the battery dies, and you have to pop-start it. And if you read my whole post, you would have read that I said the "preffered way" which i should have said right way to check it would be to use a voltmeter on the battery. Just because a method is "old school" doesn't mean it doesn't work. total rubbish! arfcom told me honda's and toyota's never break 
i keed i keed! |
|
Quoted:
Quoted:
Quoted:
Quoted:
Quoted:
Quoted:
Most auto parts stores will check the alternator and battery for free. Jump start the minivan, go there and proceed according to what they find. Otherwise, if you can't start it, change out the battery, then head to the auto parts store. If you jumpstart it with a bad battery, it wont run for very long at all, not even a few minutes. The Computer needs a set voltage to signal things like injectors and coils to operate. If the voltage isnt there, it aint gonna run. Not sure on where the battery is placed on a newer Honda mini-van, but be prepared to get the wrenches out along with the owners manual to find it. That is complete and utter bull shit. I've run many OBD1 and OBD2 Honda's on nothing but the alternator..Alot of race cars do this to drop 20-30 lbs instantly..start the car with a jumper pack and make sure you don't shut it off. you can jump the existing battery or even take off the battery terminals and hook them directly to the jumper cables, start the car, unhook the jumpers and if the alternator is good..the car will run fine..until you shut it off and it needs to start again. And thats one way to field test an alternator. Get the vehicle started and un hook the battery..if the idle drops drastically or the engine stalls..the alternator is bad or is on the way out. The preferred way is to test the terminals on the battery (or without them on the battery) with a voltmeter. anything above 13 volts with the engine running will work. And alot of people will armchair that this won't work or its a bad idea on a NEW car, which it probably is..but i've done it..many-a-time. One main reason to back that up is the power wire running from the alternator runs DIRECTLY to the positive cable coming off the battery..with more voltage than battery has. If the car is running, It won't make a difference if there is a battery there or not..until you shut it off. Some vehicles have strategy built in to where the PCM will not command the alternator to charge if the static battery voltage is below "X" amount. This is because trying to charge a discharged battery with an alternator is very, very hard on the alternator; alternators are not designed to charge dead batteries. Of course, you're the one advocating pulling battery cables while the engine is running. With all due respect, I don't think you have the right to call bullshit on anyone with that asinine recommendation. I know, I must have been hallucinating working on all those Honda's. Honda's have an ELD or electronic load detector. It adjusts the field strength in the alternator(Also adjusts the idle up and down when you are playing with things like AC and the radio) depending on what the current draw is coming off from the battery. But they have a fail safe if the main battery fuse blows, it won't kill the car. which is why the ELD is after the main power cable(And after the alternator voltage input) in the fuse box on a Honda. It won't kill voltage coming from alternator. Only reduce it. What you are referring to is a crowbar circuit and there aren't that many vehicles out there with those, for the simple fact that it will leave you completely stranded if the battery dies, and you have to pop-start it. And if you read my whole post, you would have read that I said the "preffered way" which i should have said right way to check it would be to use a voltmeter on the battery. Just because a method is "old school" doesn't mean it doesn't work. total rubbish! arfcom told me honda's and toyota's never break
i keed i keed! Yeah, and if you were to believe everything arfcom said, 95% of the members here make DEEP into the six figures yearly, have pussy banging down the door, and has seen more "shit" than Patton himself.
|
| In case you disconnect the battery and do not have the codes to unlock your nav or tunes, you can get them here online. |
|
When you're hooking the new battery up, connect the positive (most likely red) terminal first. Seriously. To simplify the explanation, current flows from negative to positive. Give it somewhere to go before you let it out. Otherwise you could end up with a surge and fried electronics. The reason batteries seem to die "instantly" these days has to do with how much power they actually store. You could have a battery that's only 40%, and it will still crank your engine over just fine. Then, all of a sudden you have a cold night, and bang. You lose that last little bit and you have a dead battery. The battery was actually bad for a while, you just didn't know it. And don't ever disconnect a battery while the engine is running, unless it's an OLD car with a GENERATOR instead of an alternator. You can fry stuff that way, too. The battery, even if it's no good, still acts as a resistor, and helps prevent voltage surges. edited to add: in either case frying your electronics isn't likely, but it's possible. So don't disconnect the battery while running the engine, and when you're replacing a battery, always disconnect negative first, and always hook up positive first. |
|
Quoted:
When you're hooking the new battery up, connect the positive (most likely red) terminal first. Seriously. To simplify the explanation, current flows from negative to positive. Give it somewhere to go before you let it out. Otherwise you could end up with a surge and fried electronics..... Not true. It doesn't matter which way you hook up the battery. Until you connect the second terminal, the circuit is open and current can't flow. When you connect the second terminal, the circuit is now closed and current will flow. No different than using the power switch to turn on the radio. |