Ok so for awhile my truck wouldn't start. Almost every morning I would have to jump it to get it going. It had a red top so it was a good battery. Finally we took it in and tested and the battery was bad. We picked up just a middle of the road quality battery and put it in last night. I wake up this morning and the same problem. It won't start and I need a jump. What is going on????? It will sometimes start now but I don't know if the alternator is bad or something is draining it. I have nothing hooked up straight to the battery. Only stock.

ohh truck is 85 toyota pickup. 4 banger

thanks

 

any ideas?

 

I would check the alternator, most local parts store can check them to see if they are good. But check the fuse first, I had a blown fuse and had the same problem. If the alt. checks out good, start looking for bad wires.

 

Sounds like a charging problem. Check your connections to your alternator. There may be some corrosion around the terminals and may be causing the alternator to discharge the battery.

 

If you put the battery in one night and it was dead the next morning depending on how long it was driven after installing the battery, you've likely got a parasitic draw on the system like dome light, radio, etc. left on, an alternator / regulator issue causing the battery to either not charge or discharge through the regulator or some issue with the wiring or other devices like main relay or similar staying on when you turn the key off.

You'll need a multimeter to accurately troubleshoot.
With the engine running and nothing else turned on, battery voltage should be more than 13.5 and less than 15. If that's good, the system is charging and you have something discharging the battery. You'll have to go in and pull fuses, etc, until you find what's causing the drain with the key off- if you put the meter in amperage mode you should be able to pull a fuse and then insert the probe leads in the fuse holder and see if the circuit is drawing current... and make sure the meter can handle the current- if it can't you may be able to use a test light to see if current is being pulled.

 

dude 85RunnerSR5 thanks but i totally feel like an idiot. i checked the connections like u said and one was loose. now it starts up everytime. Thanks again

 

Hey man, it happens. Glad we could help you out!

 

You might try getting a battery terminal cleaner($3) and cleaning the posts and terminals good then coat all with Vasilene and reconnect.

 

Really, vasaline huh? Does that work just as well as the electrical grease that I can't remember the name of that costs 10x as much?

 

Vaseline, chassis, dielectric and most other types of grease are insulators and really shouldn't be used on electrical connectors, though spreading it over the connections after they're made will help keep corrosion down. A better choice is one of the products you can get at electrical supply stores (home depot even) such as KopperKote, Noalox, etc. made specfically for connecting dissimilar metals and inhibiting corrosion, and some types of anti-seize lubricant as well. The small squeeze bottles are usually a couple of bucks. We use those type of products on electrical conductors at cell sites and I've seen some that after removing the terminals from sites' back-up batteries, the bar under the connector looked brand new and not a hint of corrosion after 10 years.

 

Yeah good post. Auto stores have a red spray but I think it's messy. Also there's those red and green felt washers that are supposed to reduce corrosion but I like Vasilene. It works well to block air/oxygen and is cheap and readily available.