electrical problem with car need help badly!!

[Adriaan]

So here the problem. For the last few month been having this problem. the battery light would come on. When to the dealer waste of money they said it was the alternator. They never gave me much details, never checked the battery, electrolytes etc .
Anyways this is what i was able to find on my own. Now when the car is off the battery is 11.85 v to 12.36 v depending on the day when the alternator is doing it job the battery is at 14v when the battery, airbag & abs light come on the volts at the battery are 0. when the lights start to flicker the volts are about 10 and start to climb cuz it charging the battery. Also at the same time the headlight get bright & dim. but the tail lights and interior lights are not affected. When its charged back to normal 14v & all the battery etc. lights are off every so often all the lights in the car dim and brighten headlight tails interior etc. I'm not sure if it the battery with a bad cell or low electrolytes, or the alternator with worn brush, volt regulator. or both the battery & alternator are going. I though it was the amp disconnected it but it still happens. Nothing else is attached to the battery.
When i did the test the radio, fog & amp where off the car is a 2006 with 110000 km i cleaned the poles and the connectors with sand paper then contact cleaner. and covered them again with pole protector liquid. I was thinking maybe it could be dust from work in the alternator but i'm not sure anymore. Also don't want to waste extra money for no reason when it not the problem. Any ideas on what it could be. If you need any more if let me know.

[Reddog99]

I can't help you with your problem Adriaan, but your post would be a lot easier to read if you broke it up into paragraphs. As it is right now, it's real work to read.

[floydisrock]

All the battery does is start the vehicle,once started the alternator runs the electrical system.
Sounds like the alternator.

[talnlnky]

with your car off, your electrical system should read 12.2-13.2volts (this is your battery resting voltage)

when you turn on your car your alternator kicks in and your electrical system should reading 13-14.4volts.

problem is... if your alternator is going out it might be producing around 14volts... but at a VERY low amperage... thus, with out a Clamp meter/ammeter (measures amps) you won't know. a normal DMM can't measure amps.... well.. they can... but not the 70+ amps that you would require.

without an amp clamp you can't tell for sure if your alt is really dead or not

[CTScott]

So here the problem. For the last few month been having this problem. the battery light would come on. When to the dealer waste of money they said it was the alternator. They never gave me much details, never checked the battery, electrolytes etc .
Anyways this is what i was able to find on my own. Now when the car is off the battery is 11.85 v to 12.36 v depending on the day when the alternator is doing it job the battery is at 14v when the battery, airbag & abs light come on the volts at the battery are 0. when the lights start to flicker the volts are about 10 and start to climb cuz it charging the battery. Also at the same time the headlight get bright & dim. but the tail lights and interior lights are not affected. When its charged back to normal 14v & all the battery etc. lights are off every so often all the lights in the car dim and brighten headlight tails interior etc. I'm not sure if it the battery with a bad cell or low electrolytes, or the alternator with worn brush, volt regulator. or both the battery & alternator are going. I though it was the amp disconnected it but it still happens. Nothing else is attached to the battery.
When i did the test the radio, fog & amp where off the car is a 2006 with 110000 km i cleaned the poles and the connectors with sand paper then contact cleaner. and covered them again with pole protector liquid. I was thinking maybe it could be dust from work in the alternator but i'm not sure anymore. Also don't want to waste extra money for no reason when it not the problem. Any ideas on what it could be. If you need any more if let me know.


Check out the 07 TSB "Charging System Warning Light". It is in regards to an issue where the charging system warning light may illuminate
due to a corroded connection on the voltage regulator of the alternator. It details the inspection procedure:


http://www.yarisworld.com/forums/showthread.php?t=9753&highlight=tsb

[YarisSedan]

Not really true, if you disconnect the negative side of the battery with the car running and it dies then your alternator is junk. This little tip will save you the money and time of removing the alternator to have it tested.

My guess is that your voltage regulator is on the fritz or you have a bad diode in the alt. I am not sure if the voltage regulator is in the alternator on these cars or not but I do know that removing the alt on theses cars is not very fun, the bottom bolt is a pita to get to.

If you still have a warranty take it back in and tell them to replace the alternator since they know it is bad!!!!! This is covered under 3 year 36,000 mile in the US.


That is a old school mechanic trick that is for pre obd2 cars 96 and below. I would not attempt disconecting and reconecting the battery while the engine is running as you can seriousely damage sensitive sensors as well as the pcm.

You obviously have a volt meter as you are able to measure engine voltage with the vehicle off as well as engine running. Here is a trick you can do. Hook up your meter with the vehicle running. Turn on all heavy load accesories. Such as headlights with high beams on. Rear window defroster. Radio and lastly a/c. Monitor your system voltage as you turn each on. If things start to slowly drop then you have a problem with your altenator.

Your battery light comes on i think when it detects system voltage below around 11 volts with the engine running. Meaning you have a charging system problem. I am a mechanic and id say about 90 percent of all cars that come into my shop with battery light on require altenator replacement.

If the altenator tests okay you would need to perform a load test on the battery. Easily done but putting on a load such as headlights and defroster. Wait a few minutes and go in and attempt to start the car. If it just clicks then you more than likely need a new battery.

If id have to guess the lifespan of our factory battery is probally 3-4 years. 5 at the very most.

[YarisSedan]

You can disconnect a battery while the car is running without damage in odb1 and odb2.

What sensors would you damage? What sensors are hooked up directly to the battery?

The battery only starts the car and is used if needed for extra draw. The alternator is designed to run the car and all of its accessories that come from the factory and charge the battery if needed.

The op has already stated that he has checked the voltage while the car charging and and with the car off. I stand by my statement above and if you want an easy way to tell if your alternator is junk disconnect the negative side terminal with the car running. His problem is intermittent which leads me to my assessment above that he his voltage regulator is on the fritz or he has a bad diode in the alternator. I don't know if the voltage regulator is in the alternator in this car or not :iono: (probably is). One way or another I would bet he needs a new alternator.

If you dont belive me you will find out the hard way. When i went to school years ago this was something that was taught to us. Also ill tel lyou first hand experience one of my lube techs was changing a battery for a car i forget what kind it was i just remember it was a suv of some sort. He left the key on. After he was done the check engine light was on as well as abs light was on.

When you put the cable back to the battery you will see it spark if the key is on. This has the potential to surge and possibly damage sensors as well as the computer. True there are fuses but sometimes not everything is protected. I still would not try it.

[CAJUIN]

no no no its a fuse it happened to me, all lights came on and my batt would die out trust me its a fuse, check your fuses mt a/c would also not work. I took my altern6ator out charged my battery, the works it was one lil fuse check them

[YarisSedan]

Here's the short and simple of it. The alternator produces electricity and the amount it produces is determined by the voltage regulator. The voltage regulator determines how much electricity is needed by monitoring the battery voltage. A battery is like a sponge for electricity. When discharged the voltage is low and it's like a light weight, dry sponge and will "soak" up lots of electricity. When it is fully charged, the voltage is higher and it's like a sponge soaked full of water, heavy and unable to soak up more. Try to put too much electricity into a fully charged battery and it gets hot and boils the water out, just like that full sponge dripping out water.

When the engine is running and you disconnect the battery, the voltage regulator senses very low, actually no voltage, and tells the alternator to produce as much electricity as it possibably can. Instead of the voltage being regulated at around a maximum 14.7 volts like normal, it shoots up to around 18 volts, all the alternator can produce. That fries bulbs, voltage regulators, ignitors, fuel injection components and so on. Even a totally dead, non-operative junker battery will soak up electricity (unless bone dry)and keep you from frying the electrical system, it just won't hold a charge, just like a bucket with a hole in the bottom.

[YarisSedan]

Best way is take it to a reputable shop. They throw it on a tester that tests your battery and altenator for you and prints out the results. It seems for some reason I get a lot of dealership cars that are improperly diagnosed. Or they dont know how to diagnose the car so they throw parts at it. Example a volkswagon jetta came in with drive by wire system. Had engine code and when i sourced alldata there are 3 possibilities that could set the code as it dealt with the drive by wire system. The throttle assembly, the sensor located on the gas pedal that sends the signal to the throttle assembly or the maf sensor. I tested all 3 and found only the maf to be faulty as it was reading only 2 grams of air at idle and barely went up when the throttle is opend. Total cost of repair to customer was approx 400 dollars. She was quoted at the dealer 1800 dollars. As the morons did not know how to test each component or did not want to take the time as it was lengthy and parts had to be removed. So they just told the service writer pretty much to sell the entire job. Depending on who owns the dealership they may be on flat rate as well as comission bonus. So the mechanic is getting paid a hour diagnostic if the job takes 1.5 hours to fully diagnose. As opposed to if he takes 10 minutes to just calculates the the possible options and then recomends them to be replaced. He now gets paid 1 hour for 10 minutes of work.

As opposed to taking it to a shop where the mechanic is paid hourly so he is going to take his time. Perform a good job because come backs may cost him his job as well as reputation. And save a lot of money on the diagnostic as well as repair.

I don't know why so many people still belive that if you take your car to the dealership you are going to get the best work done. Unless your getting your car worked on by the lead mechanic which probally wont hapend. Its going to be worked on by one of his apprentices. So pretty much they are practicing by working on your car.

When you could have it worked on by a journyman

[ddongbap]

Aren't electrolyes something you eat?

[Shroomster]

UPDATE ADRIAN?

[CAJUIN]

dont make something out of n6utthin6g check the fuses first

[Adriaan]

sorry for the delay, well the problem is still unknown. Waited till the problem came back since it was intermittent. When they did the test with a multimeter, under heavy load the alternator max out at 13volts. Now here the weird part if you separate the two, battery & the alternator they work great. ie new battery with old alternator, new alternator & old battery etc. When they when back together in the car there working find but the lights are still on!! So we left it in the heated garage over night and the lights when away, and haven't come back since. Still watching it to see if it either rain or snow will set it off again. It has to be a wire that is braking down internally, or moister is the problem. i'll keep you posted on events.

["G"]

Check out the 07 TSB "Charging System Warning Light". It is in regards to an issue where the charging system warning light may illuminate
due to a corroded connection on the voltage regulator of the alternator. It details the inspection procedure:


http://www.yarisworld.com/forums/showthread.php?t=9753&highlight=tsb

Has anyone successfully replaced the regulator in this tsb?

[beZzZ]

Has anyone successfully replaced the regulator in this tsb?

Adriaan has done it, and get the problem solved. If you want details how it's done, I can PM you the way he taught me to fix it.

["G"]

Yes please.

["G"]

Has anyone successfully replaced their regulator or removed the corrosion? It looks to be a $140 part > http://www.toyotapartszone.com/oem/toyota~alternator~assy~27060-21150.html

[swidd]

I thought I had an electrical problem a while ago. Turned out I was fooled by a cheap Uncalibrated multimeter that wasn't reading right. Just sayin

[beZzZ]

Has anyone successfully replaced their regulator or removed the corrosion? It looks to be a $140 part > http://www.toyotapartszone.com/oem/toyota~alternator~assy~27060-21150.html

on the website, it stated the part is $431.97.

Also, the dealer place quote me a price of $700 to get it changed, a brand new one including labour.

Apparently, Adriaan told me 06-08 Yaris alternator more likely to have this problem. but the 09 one is improved and upgraded.

[Adriaan]

Ok here the update of that electrical problem I had. Which is solved now.

The big problem is the regulator. If it is taken to a shop they can't pick it up since it isn't under the same load and condition as on your car. I've tried even when the problem turned constant. Toyota couldn't pick it up. Also the regulator is a dealer part only. Shop may say they have but the part alone from the dealer is 275$. So if the rebuilt it for 150$ they didn't change that part or got one from a scrap yard with less kilometres.
So here the fix. If you can get an alternator from a 2009 and up. There a few 09 in the scrap yards now check http://car-part.com. The 06 to 08 have this problem, and toyota know about it there a TSB out about. But they don't tell you the problems it causes if left unattened. The dealer will try to sell you one for 06 to 08 and say the 09 won't work but it does the internal design is different and improved. Get a used one i think new from the dealer is 800$. Once it has a year warrenty you'll be find. If the casing or pulley is damage on the 09 its ok, once the inside is good. The 06 casing and pulley are the only parts that will transfer.
Changing the regulator from a 09+ into your 06 alternator works fine and first but over loads the alternator wire to the battery terminal and melts it. It overcharge and undercharge the battery to the point your not sure which one is failing, and they both fail at once.
Here are some steps I did while i was installing the new alternator. Check your postive battery terminal harness. Make sure the clear fuse is still good i think it 60 & 120amp. Make sure the poles on the black plastic are clean for good contact. The side one goes to the starter and the back goes to the alternator. You'll see where the wire connects to those terminal a bit of the cooper wires are exposed, if you can try to cover off that exposed part. Either with the die electric grease, liquid electric tape, battery terminal grease, anti seize what ever you can get or have. If not over time the condensation will spread down those wire and cause problems later. Had that problem also! Remove battery terminal from postive pole and if you can unclip the back part where two plugs there a bunch of wires there and put die electric grease, alot of moisture gets collected there, and give false reading if it not getting a good connect. Which lead to spending on other stuff which isn't the problem.
Once that is good get the alternator and put the die electric grease again on the pole of the alternator and the wire that connects it. Hope that helps. Spent over 1000$ with new battery, wires, alternator etc.
Since then i've done 20000km with the 09 alternator and it runs great. Smoother than the original 06.
Hope that help everyone, This is based on my opinions, expernices and results.