|
12-16-2012, 06:47 AM | #1 |
metallic green vitos
|
voltage...
my friend of mine is worried about some issue with his voltage. he got 1.0 auto 2001 yaris 4 cylinder. on normal idle his voltage is 13.5 but it will increase to 13.7 when rev the engine. when he turns acceseries on, like headlamps , heater blower and hazard lights, it goes down to 12.9 volts on idle, with 13.0 on reving....i noticed too that his battery is on black mark, means it need recharge....think it is from the battery or alternator problem? i almost forgot to say, when he stops on idle u switch on the hazard lights, his car it will go like rev up and down gjust a little bit and the gauge cluster will dimm a bit and bit on again. any answers? thanks and happy holidays.
|
12-16-2012, 08:48 AM | #2 |
ULTIMATE
Drives: 09 5dr LB, 2x 08 3dr LB Join Date: Oct 2008
Location: USA, CT
Posts: 13,460
|
It definitely sounds like either the alternator is not working properly and that the car is primarily running off the battery, which is why the battery is now run down as well.
__________________
|
12-16-2012, 08:59 AM | #3 |
metallic green vitos
|
youer sayin that the battery is not chargin cause of alternator not workin good?
|
12-16-2012, 02:04 PM | #4 |
ULTIMATE
Drives: 09 5dr LB, 2x 08 3dr LB Join Date: Oct 2008
Location: USA, CT
Posts: 13,460
|
Correct
__________________
|
12-16-2012, 06:16 PM | #5 |
Drives: 2009 5-door, 5-speed Join Date: Sep 2011
Location: White Rock BC
Posts: 687
|
Chicken or the egg?
A bad battery can draw down on the alternator keeping it from producing full voltage. Charge the battery (or temporarily replace with a known good one) and check your voltage again. Either way you want to have the battery charged because if you replace the alternator, the new one will overwork itself trying to charge the low battery. It is only meant to top-up the battery, not fully charge it. I would guess it is the battery in this case but hard to tell from several thousand km away ;) Cheers. |
12-16-2012, 07:10 PM | #6 | |
ULTIMATE
Drives: 09 5dr LB, 2x 08 3dr LB Join Date: Oct 2008
Location: USA, CT
Posts: 13,460
|
Quote:
__________________
|
|
12-17-2012, 01:35 AM | #7 | |
Drives: 2009 5-door, 5-speed Join Date: Sep 2011
Location: White Rock BC
Posts: 687
|
Quote:
Cheers. |
|
12-17-2012, 06:52 AM | #8 | |
ULTIMATE
Drives: 09 5dr LB, 2x 08 3dr LB Join Date: Oct 2008
Location: USA, CT
Posts: 13,460
|
Quote:
__________________
|
|
12-17-2012, 11:01 AM | #9 |
metallic green vitos
|
intresting about the chicken or the egg mate..i like that....yesterday i went to check out his voltage again. got an expensive multimeter to make sure it reads good. so good i tested the battery first, it reads 12.4 volts. then i started the engine. then from the battery termimals, it read 14.0 to 13.9 that for me the alternator hes doing his job. switched the heater on and headlights to bright, no trouble, still 13.9, BUT!! his engine it like shakin a bit, i guess it is normal. he drive up for one week, but battery stays on black indicator, i guess it time for changing it. btw it is 7 years old. anyone knows what voltage should the alternator gives?
|
12-17-2012, 11:13 AM | #10 |
metallic green vitos
|
btw, i got haynes about yaris, it tells that should be 14.0 volts. but i never depend on this book, i like other people answers.
|
12-17-2012, 12:52 PM | #11 |
Drives: 2009 5-door, 5-speed Join Date: Sep 2011
Location: White Rock BC
Posts: 687
|
Alternator should put out around 14.0V at idle, no load. With how low the Yaris idles, you might see lower though so may want to do testing at slightly higher RPM. I'd say no lower than 13.5V and no higher than 14.5V is normal. The more loads you have on, the less likely the alternator can keep up. If your radiator fans and rear defrost are on, chances are you are running off battery. No way the alternator can keep up to all that current draw. To properly test the charging system you need a "carbon pile load tester", but this isn't something most people own ;) Voltage is only one part. Amperes are just as important.
End of the day I would guess all is working correctly, but at 7yrs old it's probably time to get a new battery in there anyhow. Cheers. |
12-17-2012, 03:24 PM | #12 | |
ULTIMATE
Drives: 09 5dr LB, 2x 08 3dr LB Join Date: Oct 2008
Location: USA, CT
Posts: 13,460
|
Quote:
__________________
|
|
12-17-2012, 04:06 PM | #13 |
metallic green vitos
|
thanks for replies. no ct scott. im not seeing 12.9 now....maybe the other volt meter got screw or whatever....tried 2 different volt meters and they read the same 14.0 and 13.8/9 on load.
|
12-17-2012, 06:51 PM | #14 |
ULTIMATE
Drives: 09 5dr LB, 2x 08 3dr LB Join Date: Oct 2008
Location: USA, CT
Posts: 13,460
|
That is definitely fine. Depending on the brand of battery, seven years is a reasonable life.
__________________
|
12-18-2012, 11:02 AM | #15 |
metallic green vitos
|
magnetic is the brand, and trust me or not, that battery was used so hard for five years. even was on a hyundai accent with 2.0l turbo with 2k sound system...i guest now need to go to junkyard ;)
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Electrical System Upgrade Advice | sqcomp | In Car Entertainment + Electronics (audio / video / alarm) | 6 | 03-23-2016 01:15 AM |
Voltage reading from SG | The Spectacle | In Car Entertainment + Electronics (audio / video / alarm) | 21 | 08-27-2011 12:33 AM |
NEED ENGINE CHECK LIGHT CODE LIST | Attitude | Forced Induction Forum | 12 | 04-11-2011 06:38 PM |
Voltage regulator and Amperage question... | cr.chango | DIY / Maintenance / Service | 13 | 11-24-2009 12:59 PM |
High voltage | -m- | DIY / Maintenance / Service | 7 | 08-01-2007 09:48 PM |