Negative battery cable disconnect

[smashman]

2001 RT/10

Hi guys, I am planning to replace the current aftermarket stereo which is over 20 years old with a new one that has inputs for USB, etc. Is there any way to disconnect the negative battery cable other than jacking up and removing the rear wheel? Could likely manage without doing so as it should just be the one battery wire to the head unit that would be hot, but would prefer not to take any chances.

Thanks in advance for any insight!

 

[efnfast]

install a battery cut-off switch in the trunk while you're there - now you can disconnect the negative without having to go through the typical BS of wheel removal

Flaming River FR1003 Flaming River Big Switch Battery Disconnects | Summit Racing

Free Shipping - Flaming River Big Switch Battery Disconnects with qualifying orders of $109. Shop Battery Disconnect Switches at Summit Racing.

www.summitracing.com

 

[smashman]

That is a very good suggestion. I assume that means for now, the only way to disconnect the negative for my purposes is to remove the wheel and do it that way?

 

[luc]

2001 RT/10

Hi guys, I am planning to replace the current aftermarket stereo which is over 20 years old with a new one that has inputs for USB, etc. Is there any way to disconnect the negative battery cable other than jacking up and removing the rear wheel? Could likely manage without doing so as it should just be the one battery wire to the head unit that would be hot, but would prefer not to take any chances.

Thanks in advance for any insight!

It only take 5 minutes to remove the wheel and the access panel
Took you more time to post than doing it

 

[smashman]

I'll accept that as a fair shot. I always seem to have a fight getting the panel back on so was just hoping to avoid it if possible.

 

[efnfast]

That is a very good suggestion. I assume that means for now, the only way to disconnect the negative for my purposes is to remove the wheel and do it that way?

yes

it's a gigantic pain in the ass that's why I put a cut off switch in the trunk (left side, about half-way between the tail-light and the amplifier) ... then just open trunk, flip switch, done

it takes longer to get to the battery than it does to put in a cut-off switch ... the hardest part is making a new negative battery cable to go from the battery to the switch (at least it was for me since all my tools are for top-post batteries and this uses a sidepost connection)

 

[daveg]

If you need some custom cables made, this place is awesome

Quality Copper Battery Cables Made in the USA! - BatteryCablesUSA

www.batterycablesusa.com

I had some 1/0 made for my 69 Vette and the car never started better. They will put any ends on the cables you want.

 

[smashman]

Thanks guys. I'll be ordering one of the switches and that will get done. Is the negative cable 1/0 AWG? Because I already have some really good 4 gauge cable and and I could easily use that to build the extension. But if it requires 1/0, I'll get that. When I install it, can I get to the existing negative cable end from inside the trunk, or does it route to elsewhere off of the battery?

 

[smashman]

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Ahhhh....Now I think I see. So I'll need to have a longer cable built to come off of the battery which would go to one terminal on the cutoff switch in the trunk. And another to come from the other terminal of the switch back to the grounding point. Correct?

 

[white out]

Correct.

 

[Goggles Pizano]

You do realize that each time you turn that switch off you will have to have the PCM relearn right?

 

[smashman]

What does that entail? Is it a difficult process? I'd assume it's the same thing each time I would disconnect the negative cable, or is there some difference?

 

[efnfast]

Thanks guys. I'll be ordering one of the switches and that will get done. Is the negative cable 1/0 AWG? Because I already have some really good 4 gauge cable and and I could easily use that to build the extension. But if it requires 1/0, I'll get that. When I install it, can I get to the existing negative cable end from inside the trunk, or does it route to elsewhere off of the battery?

I would go 2ga minimum even though the factory used 4ga

What does that entail? Is it a difficult process? I'd assume it's the same thing each time I would disconnect the negative cable, or is there some difference?

You turn the car on and drive it. If you notice a difference with how the car drives just because you cleared its adaptive memory your tune is ******.

 

[maverickagm]

The obd2 system on your 2001 might be quicker to learn. I've had a few obd1 cars that would take a few trips to readjust the air fuel ratios. The worst thing that ever happened was my 93 ford probe stalled when rolling to a stop. Not a big deal.

That being said, If you're just installing a stereo head unit, it's much easier to just pull the fuse for it from the fuse panel. If you're running new wires for a new amplifier and what not, then yeah, pull the negative wire from the battery.

 

[maverickagm]

Also, there are ways to get usb and bluetooth on old stock head units with cd changer controls. If you're interested in that alternative, I could tell you about it. I have a black box with a usb and sd card slot in my glove box. It works on the tape deck in my 93. It uses the rca audio inputs and the cd changer din connection on the back of the deck.

If you're not, I get it. Some people lime these old school OEM (Alpine) units though.

 

[smashman]

The obd2 system on your 2001 might be quicker to learn. I've had a few obd1 cars that would take a few trips to readjust the air fuel ratios. The worst thing that ever happened was my 93 ford probe stalled when rolling to a stop. Not a big deal.

That being said, If you're just installing a stereo head unit, it's much easier to just pull the fuse for it from the fuse panel. If you're running new wires for a new amplifier and what not, then yeah, pull the negative wire from the battery.

Also, there are ways to get usb and bluetooth on old stock head units with cd changer controls. If you're interested in that alternative, I could tell you about it. I have a black box with a usb and sd card slot in my glove box. It works on the tape deck in my 93. It uses the rca audio inputs and the cd changer din connection on the back of the deck.

If you're not, I get it. Some people lime these old school OEM (Alpine) units though.

Thanks for the replies. Yes, I remember now mine relearns very quickly from just a short drive. I figured this out when my battery completely died a couple years back, and as soon as I put the new one in I went for an emissions test and it failed. I drove it around for about 10 minutes and went back and it passed just fine. As far as the head unit replacement, I did disconnect the negative just in case and it drove just fine this evening.

I actually already had an aftermarket unit, a really nice Pioneer from 2001 with the CD changer, which used an IP-BUS cable to connect to the deck. I know I could have used the IP-BUS cable with an Iphone or player either bluetooth or direct but I could not figure out how to use it to play from a USB using the deck controls, which I what I prefer. Both Pioneer and Crutchfield told me the deck wouldn't read from a USB, much less be able to control it, maybe I should have asked here as well. In any case, the swap is done and was super easy and I went with a Kenwood.

Speaking of amps and wires & mounting, I am going to add a Matrix Plus pre-amp to my setup. I have one in my truck and it's fabulous. My two amps are mounted in the trunk vertically on the front wall above the spare tire. The Matrix will fit nicely on that flat spot to the right of the amp pictured, even with the amp endcap installed. I am wondering if you know if it's safe to use a short screw or two there to mount the Matrix, or is the gas tank right up against there? If not, I'll either use some Velcro or fabricate a bracket that could attach to the wood the amp is mounted to, as the Matrix is light, only about 2 lbs.

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[smashman]

I would go 2ga minimum even though the factory used 4ga



You turn the car on and drive it. If you notice a difference with how the car drives just because you cleared its adaptive memory your tune is ******.

Thank You. I plan to order some 1/0 extensions from Battery Cables USA as suggested above. Hopefully they'll have an end that attaches to the battery post that will be the same as the OEM one.

 

[yzf1999]

Just pull the interior light fuse in the fuse panel…this will kill power to the radio. I did this when I aligned my doors so the interior lights wouldn’t drain the battery. When I finished and put the fuse back in the radio station presets had to be reconfigured, so the fuse must of cut power to it also.

 

[efnfast]

Thank You. I plan to order some 1/0 extensions from Battery Cables USA as suggested above. Hopefully they'll have an end that attaches to the battery post that will be the same as the OEM one.

You need to specify what type of end as there are several different connection methods.

I ordered pre-made from this website since I didn't feel like buying the tools to crimp side-post terminals. They call it 'type D'

Custom Cable Builder - CE Auto Electric Supply - Automotive Electrical Solutions

ceautoelectricsupply.com

Then the other end will depend on the battery cut-off you buy. The Flaming River one above uses 3/8'' eyelets.

 

[smashman]

Thank You. That is a great site and the type D looks perfect. Is yours an RT/10? If so, I'm wondering if you might have a picture of how you mounted it that I could replicate?

 

[white out]

Zero issues having a kill switch an ECU relearn. Aside from not having to deal with dead batteries while the car sits for long periods, it is a great way for pre-99 cars to do a quick reset when the remote acts up.

 

[Tom and Vipers]

So many procedures say, "Disconnect battery." .... $#%&@#(*$

The last time I put a battery in mine was at an acquaintance's house in NV in the blazing sunlight with no shade. He was OCD about his tools and I had to ask every time I needed something (of course this was moot since I didn't know where anything was anyway.) What I remember was there were about 13 fasteners comprised of 4 types each requiring a different tool. Job nearly killed me - I don't function properly in direct blazing sunlight.

If I ever expose the battery again, I'd probably install a cut off switch. Still haven't quite ruled it out given I'm proceeding to sell Wayne's Bad Viper - would be a courtesy but then it requires drilling holes. I don't like drilling holes in cars. I'm sort of OCD about keeping cars original (*** am I doing with BV, eh? LOL) NOTE: I have a 1974 Datsun 620 "Lil' Hustler" pickup and it brings tears to my eyes that that everyone that has these trucks is ruining them with Customs. The wheels are the first to go. RE: Datsun: Baby blue (Buick engine paint clost) air cleaner is iconic which imprints the youngster and his Datsun - these new young just see the 620 as something they can f**k with. ....I digress ....vents closed. ....Apologies.

 

[SYDWNDR]

You could just cut the mufflers off, then it makes the radio obsolete...

 

[smashman]

You could just cut the mufflers off, then it makes the radio obsolete...

I'd just have to get a louder radio if I did that!

 

[smashman]

Hey Guys,

The battery cutoff switch install is done, here are some pics and some info on the process. I didn't get any pics in the battery area, but that is the easiest part.

I ordered cables from: https://ceautoelectricsupply.com/custom-cable-builder/ as suggested by efnfast.

Here are the specs. I went with 4AWG as the cable from these guys is thicker than the OEM and it's super flexible. Also 4AWG was the largest they had with the same type of "D" end as the OEM one. They shipped it super fast, got them in 2 days.

Cable 1 (From Battery Terminal to Cutoff switch)
Type: D. Cable Length: 44" Eyelet Style, Right: Straight, Flat. Hole Size, Right: 3/8" Eyelet Orientation, Right: Same as Left

Cable 2 (From Cutoff switch to Vehicle Ground Point)
Type: A. Cable Length: 52" Eyelet Style, Left: Straight, Flat. Hole Size, Left: 5/16" Eyelet Style, Right: Straight, Flat. Hole Size, Right: 3/8" Eyelet Orientation, Right: Same as Left.
(The 5/16" goes to the ground location and the 3/8" end goes to the cutoff switch.

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For the location I chose, I was going to slide the bracket behind the fiberglass, but I felt like the top of the bracket was "above the curve" so to speak, so I cut a piece off of the top. Ultimately, I decided to front mount the bracket and used the cut off piece as extra support on the back, drilling two holes in it. Also drilled two extra holes in the bracket. This cutting and extra drilling may not be needed if you decide to front mount yours from the start, but I'd suggest at least using a piece of metal to add support on the back, sandwiching the fiberglass between the bracket and the metal support piece.

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Here are the two holes drilled. Again, if you don't need to cut your bracket, maybe you can get three holes.

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Here is the mounted unit. It comes with washers and nylock nuts. The handle goes on after the bolts are installed and has a little pin that taps in to retain it. Have your helper hold the unit from behind while tapping the pin in to reduce stress on your fiberglass.

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Here is where the two cables exit the trunk.

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It'll only let me attach 5 pics, I'll do a second post to continue......

 

[smashman]

Continued....We used a heavy duty 24 inch plenum rated zip tie with some paracord tied to it to fish the cables.

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Here is the finished mount. The cables lay nicely on the floor and are not in the way of anything. I bought some of these to cover the nuts on the switch. They don't fit perfect but they were cheap and came in a 10-Pack. Terminal Covers
Flaming River also sells ones specific to the unit. I think it's the FR1003TM. They'll certainly fit better so I may grab a pair.

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Here were the steps and some more info:
Turn cutoff switch to the "off" position.
Raise car, jack stand, remove tire, remove battery cover.
Disconnect negative cable from battery and ground point. Save the plastic cap that is on the OEM cable, the new cables don't come with one.
Fish the pointed end of the zip tie down through the small opening in the trunk where the cables will go. It goes through without much trouble, if you lay down under the car and pull back the plastic just a little, you'll be able to see the zip tie and and pull it through, making sure to leave a foot or so of paracord in the trunk. This is easier with a helper.
Now, untie the paracord from the zip tie and tie it to the two 3/8" eyelets on your cables. We put a small zip tie near the cable ends a couple inches below the knot to keep them together.
Next, carefully pull and wiggle your cable ends up into the trunk by pulling on the paracord end from the trunk side. It doesn't hurt to have a helper also guiding and pushing a little from below. This was actually much easier than expected, the cable ends came through without much coaxing needed.
Attach the 3/8" eyelets to the cutoff switch, first sliding the silicone terminal covers over the eyelet ends (if you use the covers)
Attach the 5/16" eyelet to the ground point above the battery.
Attach the battery terminal to the battery.
The cables are just the right length and fit nicely in the battery compartment. We used a couple zip ties for extra security.
Test operation.
Replace battery cover, install wheel and take a nice drive for your PCM to relearn if needed.
Hope this helps, and hope I didn't forget to mention anything.

 

[MY1GTS]

Continued....We used a heavy duty 24 inch plenum rated zip tie with some paracord tied to it to fish the cables.

You must be registered for see images attach

Here is the finished mount. The cables lay nicely on the floor and are not in the way of anything. I bought some of these to cover the nuts on the switch. They don't fit perfect but they were cheap and came in a 10-Pack. Terminal Covers
Flaming River also sells ones specific to the unit. I think it's the FR1003TM. They'll certainly fit better so I may grab a pair.

You must be registered for see images attach

Here were the steps and some more info:
Turn cutoff switch to the "off" position.
Raise car, jack stand, remove tire, remove battery cover.
Disconnect negative cable from battery and ground point. Save the plastic cap that is on the OEM cable, the new cables don't come with one.
Fish the pointed end of the zip tie down through the small opening in the trunk where the cables will go. It goes through without much trouble, if you lay down under the car and pull back the plastic just a little, you'll be able to see the zip tie and and pull it through, making sure to leave a foot or so of paracord in the trunk. This is easier with a helper.
Now, untie the paracord from the zip tie and tie it to the two 3/8" eyelets on your cables. We put a small zip tie near the cable ends a couple inches below the knot to keep them together.
Next, carefully pull and wiggle your cable ends up into the trunk by pulling on the paracord end from the trunk side. It doesn't hurt to have a helper also guiding and pushing a little from below. This was actually much easier than expected, the cable ends came through without much coaxing needed.
Attach the 3/8" eyelets to the cutoff switch, first sliding the silicone terminal covers over the eyelet ends (if you use the covers)
Attach the 5/16" eyelet to the ground point above the battery.
Attach the battery terminal to the battery.
The cables are just the right length and fit nicely in the battery compartment. We used a couple zip ties for extra security.
Test operation.
Replace battery cover, install wheel and take a nice drive for your PCM to relearn if needed.
Hope this helps, and hope I didn't forget to mention anything.

 

[GTS Dean]

FYI - every time you kill power to the ECU, it will wipe your long-term fuel adaptive blocks. It may also wipe your IAC (Idle Air Controller) stepper motor calibrations. That's why most folks will connect a battery tender.

Me? I've never done either. In Texas, I'll let my car sit in the garage for 2 months or more with the alarm off with no issues. When it gets longer than that, I'll hook up a trickle charger and flip it on the 2 amp setting to let it slow charge for about 2 days.

 

[efnfast]

FYI - every time you kill power to the ECU, it will wipe your long-term fuel adaptive blocks. It may also wipe your IAC (Idle Air Controller) stepper motor calibrations. That's why most folks will connect a battery tender.

Me? I've never done either. In Texas, I'll let my car sit in the garage for 2 months or more with the alarm off with no issues. When it gets longer than that, I'll hook up a trickle charger and flip it on the 2 amp setting to let it slow charge for about 2 days.

Everybody keeps saying this is the "problem" with battery disconnects, but who cares?

I usually leave mine connected for 2 weeks, then when i cycle the next car in throw my disconnect switch. When I come back 2-4 weeks later and power it back on, the car starts/idles/drives the same as when I put it away. Same with all my race cars.

If you can notice a difference in how the car starts/idles/drives after you cut the power then either your tune is messed up or your tune is compensating for some problem you need to fix

 

[white out]

I have never noticed an issue with using the kill switch in my '96 or '00.

For pre-99 cars (without the factory alarm bypass), it is a great thing to have if your alarm starts acting up or your key fob batteries die.