Toyota FJ Cruiser Forum banner

1 - 20 of 21 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter #1
Hey all!
I need some serious help trouble shooting an issue I have had for a long time now. I'm from a colder climate and have had issues with my FJ dying overnight. I have had the alternator tested and everyone says it's fine but have been through 3 batteries under warranty at this point. No one can figure out what is killing my FJ, I've brought it to multiple mechanics and even to O'Reilly's to have them test. Recently I move to a warmer climate (still chilly but not negative Montana cold) and have had great luck until this past day. She is dead AGAIN, WONT START. I drive it everyday too and from work. What could be causing this issue?!

It should be noted I have a door ajar light on my dash off and on due to my backdoor not depressing the sensor all the way. Another issue I can't solve.

I'm becoming frustrated with this vehicle even though I love the trails.
HELP
 

·
Registered
Joined
·
5,406 Posts
I too get a dead battery every few months. I remove it, test the specific gravity, which shows that it is low. Charge it then clean all terminals and cable ends and it's fine for a few months. If you can, check the specific gravity when it's acting up. I have a $6 tester from AutoZone.

As for the door ajar light. Have you checked the rear window? If it isn't latched the door ajar light will be on.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #3
This just seems like such a crappy problem to deal with every few months. I'm wondering if I could upgrade the battery or the alternator so I never have to deal with it again. I'll pick up a tester for sure and a new battery charger. I've moved into an apartment so I don't have a garage anymore which isn't the greatest either 😂
A friend and I actually took the door apart and fixed the window thinking that is what the issue was. But it is definitely the sensor on the door. I just can't figure out why it isn't latching tight enough to shut the sensor off ☹
 

·
Premium Member
Joined
·
1,685 Posts
Are the interior lights staying on and killing your battery? If the door ajar light is on so should the interior lights. You need to replace the switch in the rear door latch to fix this.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #5
All interior lights are off. When you say the switch you mean the whole locking mechanism? You think the sensor is fine and this would keep it closed tighter?
 

·
Premium Member
Joined
·
4,080 Posts
You need a basic understanding of the 12 volt DC system of your FJ and a Amp clamp meter to find a parasitic load while your FJ is parked and turned off.

With your amp clamp meter clamped around your 12V + lead at the battery you note the amps being used by your electrical system while everything is turned off and then start pulling fuses one at a time going back to your amp meter to see what lowers amps.
You have a big draw if your draining your battery overnight.

Do you have any aftermarket electrical devices installed? These are usually the culprit but with your door ajar light on that could be your problem also.

For the short term I suggest pulling fuses on your interior lights to see if this will save your battery overnight.
Your battery isn’t going to last long using it like this.
Electrical problems are a challenge.
 

·
Registered
Joined
·
21 Posts
If you have over 150.000 miles replace the alternator will be soon give up on you.My alternator quiet on me on my birthday and far from home at171.000 miles. Run on battery to first auto parts store and replace both battery becoase was original Panasonic and don't know if rechargeable. .Generally in any cars ovenight sitting something drain battery and must be a consummator and alternator have hot wire connection. Hope you will find what discharge battery overnight. Temperature affect any battery crank power and in your case don't take in consideration bUT don't drain battery multiple times becose will not charge.
Happen to me to other car.I have a record camera and few times I drain the battery to the point can't start the car and finally don't charge .Identical battery on 07Fj and 15 Lexus Es350.Fj last 11years and other last only 1 year after installing the recording camera and drain the battery .Someone posted great info to follow if you don't want to replace anything. Good luck.
 

·
MOAB SUPERSTAR
Joined
·
5,902 Posts
If you have over 150.000 miles replace the alternator will be soon give up on you.My alternator quiet on me on my birthday and far from home at171.000 miles. Run on battery to first auto parts store and replace both battery becoase was original Panasonic and don't know if rechargeable. .Generally in any cars ovenight sitting something drain battery and must be a consummator and alternator have hot wire connection. Hope you will find what discharge battery overnight. Temperature affect any battery crank power and in your case don't take in consideration bUT don't drain battery multiple times becose will not charge.
Happen to me to other car.I have a record camera and few times I drain the battery to the point can't start the car and finally don't charge .Identical battery on 07Fj and 15 Lexus Es350.Fj last 11years and other last only 1 year after installing the recording camera and drain the battery .Someone posted great info to follow if you don't want to replace anything. Good luck.
I had a similar problem with a parasitic drain that killed multiple AGM batteries. Set up a trickle charger whenever parked and that worked. By accident found the source of the drain (aftermarket lighting fuse block wired to “always on” vs “key on”) and now no problem 🤗
OP I would suspect the power drain is somehow related to the rear door adjar light and might be best to take it to a good Toyota dealership if you have one around (I do.... they really do exsist!).
 

·
A-Team Moderator
Joined
·
8,967 Posts
@RichJacot @JAFFJ

Rule #1, Be Nice! I suggest that you both read the rules again. Complaints were rec'd and your comments have been deleted.

 

·
Registered
Joined
·
5 Posts
Discussion Starter #12
I replaced the door switch and got the light off. However this does not appear to be the issue because the FJ sat for two days and is dead again this morning. I did find some kind of aftermarket button someone screwed under the dash so now I'm assuming some at home wiring is causing the parasitic drain. I have gone through so many batteries at this point nothing lasts which points to the parasitic drain. The button is under the driver side dash wired up into the steering column and from there I lose it. Any idea what it could be for?
 

·
MOAB SUPERSTAR
Joined
·
5,902 Posts
Can you get a pic? Wires usually run through a rubber grommet in the firewall just below the master cylinder in the engin bay - passenger side. See if you can find and then trace the same color wire to its source and take pics of it for us. Meanwhile a trickle charger (I recommend/use CTEK) hooked up when it’s at rest will save your batteries.
 

·
Admin
Joined
·
6,867 Posts
Maybe it's time to simply put in a battery switch... to completely isolate your FJ from your battery. They're simple and cheap. At least until you find the problem... sounds like it's getting expensive.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #15
I'm gonna put in a battery switch tomorrow. I leave town Tuesday and don't want to drain it again. When it warms up again I'll start pulling fuses with the volt meter. 🤙 Tomorrow I will upload those pictures as well.
Thank you everyone for the help!
It is much appreciated.
 

·
Registered
Joined
·
3,263 Posts
I replaced the door switch and got the light off. However this does not appear to be the issue because the FJ sat for two days and is dead again this morning. I did find some kind of aftermarket button someone screwed under the dash so now I'm assuming some at home wiring is causing the parasitic drain. I have gone through so many batteries at this point nothing lasts which points to the parasitic drain. The button is under the driver side dash wired up into the steering column and from there I lose it. Any idea what it could be for?
It doesn't matter WHAT it is for, remove the button and every piece of non-OEM wiring that's connected to it. The typical half-assedly done electrical system mods performed by people who don't have any understanding of electrical systems or good wiring practices are almost invariably unreliable and pose a risk to your vehicle.

To stop the useless stream of battery replacements, you MUST determine if there is a parasitic current drain when the engine is not running and every electrical load appears to be turned off. For this, with everything turned OFF, you need to disconnect one of the battery terminals and insert a digital multimeter, set on the DC AMPS scale, between the battery terminal and the battery clamp. Make sure that your meter has a DC AMPS range of at least 5A. If the current measured is less than 1A, change the range on the meter to the 1A range. There should be no more current draw than about 50ma (milliamps). If you see anything more than that, you have an unacceptably high parasitic current drain.

With the meter still connected, sequentially remove every fuse in both fuse panels until you find the circuit that's drawing current. At that point, you are going to have to refer to the FJC electrical schematic to trace that particular circuit and look for any "modifications" that may be drawing current.

The most common sources of excessive parasitic current drain are aftermarket alarm systems, remote start systems, audio amps, and lighting system modifications.
 

·
Registered
Joined
·
5,406 Posts
A couple of things... a battery switch can be good. But you'll have to reset all radio presets, calibrate the compass, and for me disable the chimes. But to help determine the problem, sure.

You can use the multi-meter inline. Just be sure to plug the leads back into the voltage/resistance plugs if you have them. I learned this after blowing a $5 fuse in the meter. When I was checking mine there was a current when I first connected things. It went away after a short time. There are some things that are active when first connected. Be it timers for door light, seat belt chimes or whatever.

Another method if you have a good multi-meter is to check the voltage drop across a fuse. Here's a link to many charts. fuse voltage drop chart - Polarity Yahoo Search Results
 

·
Registered
Joined
·
3,263 Posts
Here's a clear, step-by-step procedure for using the fuse-voltage-drop method to identify and isolate the source of parasitic current drain, assuming of course that it originates in a fused circuit. Note that you do need a high-quality digital multimeter to accurately measure millivolt-level voltages.

 

·
Registered
Joined
·
6 Posts
I also have this problem. Not the door switch , but the fact that my battery dies every couple days. I have had the battery, alternator and starter tested. Cleaned all the connections and tested for parasitic draw (drops to 0 in few seconds). I and a few mechanics are dumbfounded. I have a installed a Battery Maintainer and plug it in everyday, but this is a bandaid not a solution.
 

·
Registered
Joined
·
3,263 Posts
I also have this problem. Not the door switch , but the fact that my battery dies every couple days. I have had the battery, alternator and starter tested. Cleaned all the connections and tested for parasitic draw (drops to 0 in few seconds). I and a few mechanics are dumbfounded. I have a installed a Battery Maintainer and plug it in everyday, but this is a bandaid not a solution.
Very simple ... either your battery or alternator (or both) are defective, or you have a parasitic current drain.

Please provide your battery voltage measurement one hour after engine engine shutdown, and also with engine running at 2K RPM.

Next, describe EXACTLY how you performed your parasitic current draw measurement.
 
1 - 20 of 21 Posts
Top