2008 Tundra battery overheating & warng lights come on

While driving yesterday all warning lights came on, check engine, vsc, slip control, abs, emergency brake at the same time the speedometer stopped. When I stopped everything went back to normal. As soon as I started to again all lights came back on. Went home and popped hood found battery really overheating. Hot or touch & could hear it boiling inside. Both battery & alternator replaced 3-4 years ago. Not sure if I have some kind of short or if alternator could be bad overcharging battery. Any advice would be greatly appreciated. Thanks

 

I hope someone here can help you with this issue. My first thought was a defective charging system ?

 

Assuming you have a serviceable battery, carefully pop the covers off and check the fluid level. If the top of the plates aren't covered with fluid add distilled water to get the top of the plates submerged. Then check your voltage with the truck off (should read between 12-12.6v). Assuming that's good, start the truck and check voltage at the battery again. It should be between 13.1-14.0v. If that checks out, I'd have the battery load tested or replaced.

Did you use an OEM alternator when you replaced or aftermarket?

 

Thanks for the feedback, sealed battery but I checked the battery voltage it was right about 12.6. I'll still need to check when running. Not sure on the alternator being OEM or aftermarket. I will have to go back & check. It was replaced at a Goodyear shop about 3 years ago.

 

What kind of battery? I assume it’s AGM since it’s sealed?

 

most likely aftermarket if not done at Toyota.

 

Battery is being over-charged. Your charging system is running amuck. Hard to blame it on Goodyear if that work was done three years ago. Everything wears out eventually.

 

Don't forget to check the charging voltage at different RPM's. Alternators have multiple sets of diodes to convert the AC electricity to DC throughout the operating range. Many of the alternator failures occur in the diodes.

From my experience, when I replace the alternator I will replace the battery at the same time and vise versus.

 

Thanks great feedback, I'll be checking tomorrow. What's strange is 2008 tundra and had battery & alternator replaced in 2012 at toyota so that should / would have been OEM. Then alternator goes bad again in 2016. Had it replaced at tire shop could have been / probably aftermarket. So seems like I'm only averaging 4 years per alternator either oem or aftermarket. Does that seem normal ? Dont drive it alot only have 130,00 miles..

 

That does not seem normal. I would check all of the electrical connections in the charging system.

 

Negative, but KNOCK for me haha, I have my original alternator, and have replaced my battery once on my 08.

 

Are you sure you're not overheating?? And the boiling might be coming from the radiator?? Engine is right by the battery so it may be normal the battery may feel hot to the touch... ECU may be trying to protect the engine...

 

Thanks to all, good to have info on another "08" to compare against. Radiator looks good, not overheating, no fluid loss. Will be replacing the battery & alternator later tomorrow. Autopsy on alternator to follow. But today looks like I need to start digging into the electrical system a little deeper to see if anything looks out of norm.

 

I hope it's nothing expensive!
From previous research, it could even be a bad/loose/corroded connection on the positive battery terminal.
While you're replacing the battery and alternator, are you replacing the cables also?

 

Terminals were pretty clean & tight when I pulled battery yesterday but I will take a better look today.

 

Thanks to all for the feedback. Alternator was the problem overcharging battery. Was getting 20v from alternator back to battery. Crewmaxlmt owe you a beer. Spot on with the diodes. Went back and did my homework now I have a better understanding of what was going on. Bad diodes allowing enough ac voltage to bleed back thru electrical system causing the issues with all the warning lights. Voltage regulator in alternator not regulating voltage back to battery. That's why things got worst as I accelerated and went back to normal when I stopped. More rpms causing more voltage back thru system due to voltage regulator not working. Now i just need to check all wiring & connections to ensure no other issues. Got my GED in alternators this week. Thanks again to all for the feedback.

 

Dayum... glad you got it figured out, and thanks for the education....