any ideas for electrical problem?

C

CathyG

New member
I own a 1986 4Runner that is 4wd, 4 cylinder, and a manual. It has some serious electrical issues but other than that runs great. It has an itermmitent(sp?) electrical drain that sometimes leaves me stranded. I installed a device(Battery Brain) that is supposed to cut my battery from the rest of the electrical system if it starts to drain while I`m parked. Lately it`s decided that turning on my AC or radio while driving is draining and cut power while I`m driving, which is a problem when it`s 100+ degrees outside and I can`t get it restarted. It also doesn`t like me turning on my lights which means no night driving. Battery Brain started doing this 2 days ago. Before that it was working just fine. I`m uninstalling it tommorow and trying to find some sort of quick disconnect for my battery cables. My 4Runner was owned by a guy who installed some aftermarket accesories the first 5 years and he screwed up all the wiring. He then sold it to a mechanic who owned it for the next 15 years. The mechanic sold it to me and now I`m stuck with a vehicle that has the perfect cargo area for what I need but isn`t reliable. I`m headed to a place that specializes in auto electrics tomorrow. If the estimate is over 1k the 4Runner is going up for sale. :( There are several 1st generation 4Runners in my area up for sale without severe problems. Any ideas on a quick release thing for my battery cables? Or some other way to make it more manageable?
 
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Sorry for your dilema.

I assume you have checked the condition of the battery and the charging system and this is all ok.

I'd recommend you pull all the aftermarket wiring out. See how the truck runs then. I guessing you have an earthing problem which might turn nasty (eg a fire) if you don't sort it out.

If you have removed all the aftermarket wiring and still have the problem, I would first check all the wiring I could see/feel/reach and check for the conditon of those. As an example you might be looking for a wire that has had some of its insulation removed as a means to tapping into power. Maybe this wire is now explosed and draining power elsewhere. Secondly, having done a visual/feel test, take it to a dealer and ask them to see if they can identify the problem.

However, if you have a electrical automotive mechanic you know personally or by recommendation/reputation, this would be an excellent option also.

Hope you sort it out quickly and please post you outcomes.
 
With everything attached you should have the charging system checked. There should be a certain voltage when charging. Also a load test should be done on the battery. You may need a special battery (maybe an Optima Yellow Top) to work properly with the extra load you may be requiring.

Koz
 
The charging system is fine. It`s an electrical drain somewhere that`s causing the problem. The guy who had it the first 5 years almost completely rewired it so it`s not just aftermarket wires that are causing trouble. How do you get to the wiring to check it? I`ve found some quick release battery terminals but they`ve been in Europe. I`ll either keep looking or end up placing an international order. If anybody has ever installed a kill switch in a 4Runner, especially a 1st gen, pm me. I think that may be a more permanent solution.
I wrote down on a calendar everytime I needed a jump. Since most of those people that helped me jump my truck didn`t even know the basics it looks like I`ve taught 15+ people how to jump a car. :D I guess that`s kind of a weird benefit to having a truck like mine. You get to meet everybody from the squirmy 16 year old girl who doesn`t know the first thing about cars to the car mod guy who sits there gawking at my 4Runner and talking about lifts. I`ve only had two people refuse to help out. One of them was worried that his wife who was recovering from a stroke would try to lift something heavy and the other was a lady who was "too busy". A lot of them were amazed by how easy it was to jump a car. Battey failure is kind of common out here but only 1 person had jumper cables. That just doesn`t make sense to me.:confused: Oh well, any vehicle I ever own will have jumper cables, a container of water, and a fire extinguisher. If not for me than someone else who needs them.
 
Ok, well I'm not electrical expert by any means, but I'm thinking the best way to test the wiring for an earthing problem will be to check each wire using a resistance tester. You know the sort that is either analog (has a needle that swings across a scaled face) or a digital readout.

They are cheap to buy at places like PepBoys etc.

Otherwise take it to a mechanic.

Pity no one from your area is stepping up to help you out.

Have you checked with the guys at Yotatech. They have a big forum of early model owners. Also check TTORA and ih8mud.com forums. If you go to these other forums search for your geographic area and see what people post from that area.

Good luck

Mark
 
If this were my problem then I would disconnect the positive lead from the battery. Then I would connect one end of a multi-meter to the loose end of the battery cable and the other end of the multi-meter to the positive terminal of the battery. Set the multi-meter to amps. Measure the current draw with the engine off. It should be something like 20 to 50 milliamps (0.02 to 0.05 amps). Obviously yours will read higher. Then one by one remove every fuse. Once the amps drop significantly then one has identified the circuit where problem is. Then everything in that circuit needs to be checked out (factory service manual is essential here)
 
Do you have an aftermarket stereo amp installed? If so then remove the fuse for it first. It will be tapper off the of battery.
 
Thanks greasefingers! I`ll head out for the multi-meter in the morning. I think that will help narrow it down a lot faster. In the mean time I`ve installed quick release battery terminal things. I`ll post a pic in the morning but they look like they`ll be effective and were easy to install. Any ideas on where to get a service manual? And I don`t have any aftermarket audio equipment except for a CD player.

Expat: I`d take it to a mechanic but if I can learn how to work with an electrical issue I`d like to do it myself. I don`t mind spending money for a meter and stuff like that but I`m tired of getting the run around with even highly recommended mechanics. I like working on my car anyway.

Edit: here`s a pic
86419e3f.jpg~original
 
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You need to connect an amp probe on the main battery feed line (red + lead/wire) that shows low readings and then start disconnecting circuits/fuses until you identify the one that is draining the battery. When you hook-up the probe you should see a above normal draw. When you disconnect the problem circuit the draw will return to normal. You could get a normal reading from another 4Runner or you might find it in a repair manual. You can get a inexpensive multi-meter W/amp probe from sears. The ring on top opens and all you have to do is slide the red + wire in that loop and you are on your way.

http://www.sears.com/sr/javasr/prod...ers,+Testers+&+Accessories&BV_UseBVCookie=Yes

Koz
 
An amp clamp is the sexy way to do it, but 99% of the people that own mulitmeters do not have this additional accessory. Since they are almost never needed for motor vehicles, then I would make do without it unless you have money to burn.
 
greasefingers said:
An amp clamp is the sexy way to do it, but 99% of the people that own mulitmeters do not have this additional accessory. Since they are almost never needed for motor vehicles, then I would make do without it unless you have money to burn.
Click to expand...

$34 :confused: To find the problem instead of guessing and you get a muti-meter with a built-in amp probe.

Koz
 
Cathy - does your battery drain while sitting (not running, no key in the ignition)? If so, you can eliminate certain circuits like the radio, defroster, HVAC system, and focus on other systems like the lighting. I had a '91 Honda that had a rusted tail light socket, this created the short, and after about 3 days of sitting in the driveway (usually a long weekend) it would drain the battery (took a while to find it, but once found it eliminated the problem). Also, you should make sure that the alternator is charging at the correct load (not too much, not too little), then load test the battery. After so many drains and jumps, the battery plates may start failing, but definitely fix the short first.
 
I agree with what greasefingers and koz have said. Basically, they're telling you to find what the industry calls a "parasitic draw." According to my Toyota service manual, which refers to GM's research, most cars made after the early 80s should only have a maximum of 50 mA with every circuit off. I checked mine a few weeks ago, and it had a draw of only 26 mA if that helps any.

I cant help but wonder if it's just that your battery is getting tired. If you haven't checked it out at a local shop, have them hook it up to one of their machines and see. It's strange that that brain would shut off when you turned on your headlights. Your alternator should be producing enough voltage when the vehicle is running to keep that brain from interfering. I believe at idle, your alternator should be producing around 14.4V. If the problem is in your battery, like boston_kevin suggested, then at least it's an easy fix.

One more thing when doing the parasitic draw test: do not close any circuits when doing it or you'll probably blow the internal fuse in your multimeter. By this, I mean dont turn the ignition on, dont open any doors (dome light will come on) - nothing. Have everything off while doing this test.

Congrats on doing the work yourself, like all of us that dont mind getting our hands dirty! Let us know how it turns out.
 
My truck wouldn`t start when a guy tried to give me a jump this evening. We sat there with my truck hooked up to his Tacoma for about 10 minutes and it didn`t even try to start. This may be the last straw before selling it but I`m definitely looking for another 1st gen hopefully black. I love the color and the truck is just perfect for my needs as long as it starts. Thanks for all your help guys but I think my truck is just going to have be sold.:sobbing: As long as it started with a jump I could work around it but not starting at all isn`t going to work with all the activities I do during the school year.
 
Get a new battery. I'm sure of it. The fact that it's getting worse has me 95% convinced. Dont give up just yet, cause if that's all it needs, you're SOOOO close.

I know I've tried to boost vehicles before, and you sit there with it charging for what seems like forever, and the battery remains dead. But then you readjust the clamps on the booster cables, and it starts right back up. When you get a solid connection, you should hear the other person's engine speed drop momentarily, then pick back up.

Sorry to hear that! I know how frustrating that can be, and you just want the problem out of your hair. Those 1st gens are things of beauty. It'd be a shame to get rid of one, especially one in good condition (except the wiring :)
 
If you get a new battery and don't fix the problem, you will be right back in the same sinking boat!

Koz
 
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It had to be jump started even before we got this battery. The battery is less than 7 months old but as much as I`ve jumped it I`m going to see if I can get a new one under the warranty. The warranty lasts 96 months. It has been sitting a lot longer than usual but when we hooked up the cables the other trucks engine noise dropped down to almost nothing so I know my battery was trying to charge from being near dead. I`m going to get my mom to come over so we can let it charge longer to see if we can get it to start. She`ll be able to give me a ride to go get a multimeter and possibly return the battery. Maybe a new battery and a more powerful Jumpstart thing will buy it some time for me to get the problem fixed. I`m going to try switching back to my old battery terminals to see if that helps too.

Koz: Right now my truck won`t even start with a jump so even getting it to start with a jump would be an improvement. I also have to work with my parents on this and they`ve been great so far but if I can`t get the truck to start at all they might not see any point in keeping it around even long enough for me to track down the circuit that`s draining.

If anybody has used a battery powered jump starter for a truck please PM me.:awais: I got one but it didn`t have enough power even when it said it was fully charged. It was the Campmor brand Jumpstarter and another car got my truck jumped at that point.
 
I agree with the other comments. You say it isn't starting but is it even cranking or trying to crank over? Or is the starter relay just clicking? If so then your short-term fix is a new battery to get you started. All the draining and boosting due to the root cause problem has ruined your "new" 7 mth old. Boosting is now more difficult because the ruined/bad battery is shorting out and using up boost power that now isn't available for cranking (does that make sense?)
Once you can start it then on to the root cause. Get the multi-meter. Check the voltage from the + to - on the battey with nothing running. Now start it up and recheck the voltage. Is it signifcantly higher (13.5 or more volts?) If not then your alternator isn't charging.
If it is charging then do the trouble shooting test between the postive post and the disconnected battery clamp. Make sure everything is turned off. Set the meter to a high amperage at first because it sounds like you have alot of draw. Then move the amperage readout down one step at a time. Like was mentioned, don't open or close anything that can cause a circuit to become live/powered on or you will overload the meter.
If this doesn't detect an issue then it is back to your alternator? Do you have an amp meter in the dash or just an idiot light? Were your lights bright when you were up and running or were they dull yellow? If your truck is running and dies when you turn on the lights then I think it is the alternator. You aren't making enough juice to power even the basics and recharge the battery. Rebuilt alternators are cheaper than a whole new vehicle.
ps. No need to put quick releases on both battery posts. Just release the negative (-) side. This breaks the circuit plus it is safer. However, you want a good connection on both posts when you are running. You sound more prepared than most. You wouldn't believe how many people travel totally unprepared in the winter because they think "it can't happen to me."
 
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