2007 Tacoma Charging System/Belt Problem?

Hi Everyone....Just discovered this forum...Glad to meet you all who definately have a lot of knowledge. Heres my concern:

Had my 07 Tacoma oil changed recently. They do a few checks while changing the oil and reported my battery was OK but not fully charged. Suggested I get it checked. Took the truck to Toyota dealer who cleaned and tightened battery cables but said battery, charging system and drive belt were all fine. They said to just watch the belt for any cracking and come back when I see any cracks. However, I think I've heard the belt squeak a few times. I put a little inexpensive charging system checker into the cigarette lighter plug and have noticed that when running at highway speeds with lights and heater fan on it reads about 13.6 volts. When at idle and lights and heater fan on it will fall to 13.2 volts and the checker's "yellow" light come on. ( Green is good, yellow in the middle and red for fail) . The truck's charging warning light has never come on. Still, I'm suspicious that things may not be right because the same little checker when used to check my wifes car reads about 14.1 volts at highway speeds. Do you think the dealer just misdiagnosed or am I paranoid. Does 13.6 volts from the alternator appear to be proper for charging a 12V battery? Truck has 104,000 miles. Belt and battery have never been changed. Due to miles I'm thinking of changing the battery just to see if it makes any difference before going for a second visit to perhaps a different Toyota dealer. Any thoughts?

Thanks
Roger

 

Charging voltage is always going to be higher by a few volts. Did you have the truck running on battery for a while before driving to the shop? Maybe the drive wasn't long enough for the alternator to top the battery off. I personally dont worry about it until I have a dead battery, probably a bad habit but sounds like a wild goose chase for nothing if everything is operational.

 

Oh and welcome!

 

Thanks Tostidos: When I drove the truck to Toyota it was a 25 minute drive which could account for a good battery charge while they had it I suppose. The initial visit to the oil change place was a 10 minute drive after the truck had set overnight. I was aware that charging voltage would be higher than a battery voltage without the engine running but was wondering if 13.2 to 13.6 was considered normal output for a running engine.
Thank you for your input and your welcome too.....
Roger

 

13.2 seems a bit low but I wouldn't fret yet, 13.6 is likely acceptable. Listen for any bearing noise at the alternator. AND I wouldn't trust the cheap 12v outlet meter to give you a spot on reading. Test the voltage under the hood with a multimeter.

The battery is probably also due for a change being 100k and a 2007, which may be why your voltage drops with a load.

At any rate the only thing I'd replace proactively is that battery, if at all.

If you have a dead battery replace the battery, and once fully charged read the voltage running with a multi meter again. If you're getting consistently low readings might be time to look at the alt. Sometimes you can re-pack the bearings with grease and clean out the brushes but I've never worked on the factory alternator on these trucks so you'll have to do some research on your options. May be worth it to just replace. Shouldn't be that high of a cost if you do it yourself.

 

Thanks Maximillion. Nothing lost by replacing the battery. I'll check charging voltage with my multimeter and compare with the little tester. After that I'll just monitor things closely. I'll either build confidence that all is OK or else hopefully catch the problem if it gets worse. Thanks again. I look forward to reading other posts on this forum. I'd like to exceed 270,000 miles that my old Nissan made before I even think about replacing the Tacoma.

Have a great day everyone.....and thanks for the neat forum and information sharing.

Roger

 

it should be 14.1 V so Its either connection from alternator or alternator is going out.