Battery terminal post question

I need to jump start my 2004 Honda Odyssey after I drained the battery using an air compressor to pump up the tires. I neglected to have the engine running. The Honda battery is 4 years old so I probably need a new one? For now, I’m looking to just jump start it. I am not sure what the cable right next to the positive terminal post is but it’s interfering with me putting the jumper cable on it. Please see attached photo. What is that thing in the way and can I loosen it in order to do the jump start? Thanks.

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Does not really matter, get good contact and you should be fine.

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So just so I’m clear: anywhere on the metal on there is ok? I don’t have to have the metal clamp on the actual post itself?

Correct. You do that so in case there is a spark it won’t ignite the fumes on top of the battery. I just replaced mine at four years because it was reading about 70% and winter is coming.

The cable on the battery post goes to the starter.

The other cable goes to the fuse/relay box under the hood.

You can’t disconnect this cable. Because with it disconnected, there will be no power going to vehicle. So the starter won’t function.

Tester

go for it, it doesn’t have to be directly on the post.

The leads coming off the post should be avoided, on the nut would work, on the lead from the clamp would be fine, from the metal extra to the nut would be fine, you really want the strongest connection available, I would try to clamp to the housing under the rubber boot coming off the battery.

Next question- where is a good place to put the negative clamp on the dead battery? The top of the engine block is wrapped in a plastic so I’m not sure where would be a good place.

Connect to a bolt on the engine for a good ground.

Tester

You do not need to connect it to the battery, any ground point would work with a good connection. Like maybe an adjuster rail for alternator etc. In fact connect the pos first, find a good ground point on the engine and connect that second, that reduces risk of a spark causing an explosion due to outgas from the battery.

Thank you all. That did the trick. I was able to jump it successfully. Much appreciated

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Just out of curiosity, why do some cars have that extra cable going to a fuse box while some don’t? What purpose does it serve? For instance, my ‘09 civic doesn’t seem to have that.

The cable just splits farther away from the battery. If you trace the cable away from the battery you will see where one cable heads to the starter and the other to the fuse box.

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The main +12 volt supply from the battery services dozens of individual circuits throughout the car, so the wiring harness has to branch out here and there to reach them all. Where the branches physically occur depends among other things on where the available space in the engine compartment is located. Apparently on this vehicle there’s some available space near the battery post, so the engineers decided to put a branch point there.

In the future suggest when you are faced w/this problem to instead charge the battery overnight with a battery charger. Battery chargers aren’t overly expensive and will come in handy for you many times in the future. There’s less chance of accidentally damaging other components in your car, the other car, explosions, and personal injuries with the battery charger method.

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What’s the weather like where you’re located . . . ?

Depending on where you’re located, a 4-year old battery might still have 1 - 2 years of useful service

Here’s an idea . . . after a few days of normal driving, head over to your local auto parts store. Ask one of the counter guys to go outside and test your battery with their hand-held capacitance tester. Even if it passes, ask him to print out the results.

Why do you say “The Honda battery is 4 years old” . . . ?

I hope you’re not still buying your batteries from the dealer . . . ?!

If you’re a Costco member, buy the batteries there. The prices are excellent, and they don’t make you jump through hoops, should the battery fail within the warranty period . . . unlike some other stores

Always use eye protection when working on vehicle batteries. Batteries will produce hydrogen, which is explosive.

To help prevent explosions when hooking up jumper cables, always hook up the positive cable to the battery first. Because the grounding cable (negative) is not hooked up, it shouldn’t spark. Then hook up the negative cable away from the battery where a spark isn’t likely to be catastrophic.

To help prevent explosions when unhooking, unhook the negative cable first and then the positive one.

Newer cars have remote positive jumping terminal locations so that one does not have to hook up directly on top of the battery.
CSA
:palm_tree::sunglasses::palm_tree:

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I use a hand pump. Considering the setup time, it’s about as fast.

I do not know how a hand pump can charge a battery!

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In older cars, there wasn’t as many little electric motors, lights and electronics. Vehicles only had one fuse box and it was under the dash, so there was one big cable going to the starter and two smaller cables off the starter. One smaller cable came from the same terminal that the cable from the battery connected to and it went to the fuse box for distribution. The other came from the ignition switch to a small terminal and activated the solenoid to start the vehicle.

A lot of older cars may have had a small wire coming out of the terminal alongside the starter cable instead of one off the starter and was quite thin. It not only provided the 12v for distribution, it also provided protection for the vehicle and known as a fusable link. It could be a real headache when it blew because you couldn’t see the break through the insulation.

Nowadays the electrical load is so high that there are two or three fuse boxes, one under the hood and the wire for 12V distribution is a lot larger than it used to be

You sure you’re responding to the correct post . . . ?! :wink:

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