Confirming the TJ's subwoofer impedance is 1 ohm

Impedance is the resistance to AC, which is what audio is. You can't measure a speaker's impedance with a DC (battery powered) ohmmeter, doing so will give you an erroneously low indication which would concern anyone. Impedance depends on the speaker's DC resistance,inductive reactance, and its capacitive reactance.

Z is the term for impedance in the below formula. R is the DC resistance measured by an ohmmeter, XL is inductive reactance, Xc is capacitive reactance... all are parts of impedance.

z.gif
 
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There is no "radio choke relay", there is however a power lead from the radio that turns on with the radio to power the OE factory subwoofer. That power lead is called various things like 'aux amp', 'antenna', 'switched power'. 'amplifier turn on', etc. but unless the OE subwoofer amp input power lead receives 12v from one of those wires, the amp won't turn on. It is off unless turned on by a power lead from the radio. Take a look at my post #13 above.

Thanks Jerry,
But I looked at the OEM wiring schematic for my 2001 TJ and it doesn't show any "gray with an orange stripe". I must be missing something here. Sorry to be a pain in the a**.
 
Thanks Jerry,
But I looked at the OEM wiring schematic for my 2001 TJ and it doesn't show any "gray with an orange stripe". I must be missing something here. Sorry to be a pain in the a**.
There is no OEM Mopar subwoofer for a 2001, that option didn't become available until 2003. We don't know anything about your subwoofer or how it is being amplified. If you have a separate amplifier for your aftermarket subwoofer, you need to look at its instructions to see how to turn it on & off. We're shooting in the dark here Fyr, you're not really giving us enough information about your subwoofer and how it's powered.
 
There is no OEM Mopar subwoofer for a 2001, that option didn't become available until 2003. We don't know anything about your subwoofer or how it is being amplified. If you have a separate amplifier for your aftermarket subwoofer, you need to look at its instructions to see how to turn it on & off. We're shooting in the dark here Fyr, you're not really giving us enough information about your subwoofer and how it's powered.

Jerry,

My TJ is the 2001 TJ that has the factory sub in the center console. From what I have read, they put the factory subs in for that model year because of the 60th-anniversary edition. I suspect that if you're correct, then the PO might have installed it later on but it certainly looks factory. All the OEM connectors are there as well
 
Jerry,

My TJ is the 2001 TJ that has the factory sub in the center console. From what I have read, they put the factory subs in for that model year because of the 60th-anniversary edition. I suspect that if you're correct, then the PO might have installed it later on but it certainly looks factory. All the OEM connectors are there as well
I thought the subwoofer didn't come along until 2003 but you are correct. Though I couldn't find the information in the 2001 FSM, I did find the subwoofer amplifier's wiring diagram for the 2002 model. The power lead for the 2002 subwoofer amplifier is black with a red tracer and I'd bet it's the same for your 2001. That's the power lead for the subwoofer amplifier that you need to insure is getting power when the radio is on.
 
I was really trying to avoid getting too technically deep in the weeds of the math and science on this but I digress... It's going to go straight over 99% of most people and they won't really need to know any of it to repair their console sub system.

There were some factory console subwoofers in TJ Wranglers starting in LATE 2001 MY. The subwoofer in mine is a 2002 MY (date code 2/27/2002), with the 6 pin grey factory wiring plug harness and amplifier. It was wired slightly different than the later subwoofers of 2003 and up that have a 12 pin electrical connector. I see you found the wiring schematic for 2002 MY, I think @Jerry Bransford you are probably correct regarding the 2001 console sub wiring as well. Checking wiring color & tracers will no doubt confirm this.....

Just in case anyone needs it:

Part number for the 2002 sub enclosure inside the console is: 56038609AC

I still have the amplifier module removed from my unit with intermediate spacer heatsink less the long screws and large heatsink I re-used to seal up the back of the enclosure when I removed it in case anyone has an early model sub with a blown up amplifier in it.
 
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I thought the subwoofer didn't come along until 2003 but you are correct. Though I couldn't find the information in the 2001 FSM, I did find the subwoofer amplifier's wiring diagram for the 2002 model. The power lead for the 2002 subwoofer amplifier is black with a red tracer and I'd bet it's the same for your 2001. That's the power lead for the subwoofer amplifier that you need to insure is getting power when the radio is on.

Hey Jerry,

Yes, the wire in my TJ is black&red so I will get it apart and hook my blue remote signal wire up soon and see if that works. Thanks again for your input!
 
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@Jerry Bransford
I stand corrected as I measured the speaker in my original article so here's the result:
The factory sub was 2 Ohm per voice coil. BTL they come to 1 Ohms total. If you use a 1 Ohm per coil speaker, the resulting load on the amplifier will be 1/2 Ohm and I highly doubt it will be stable at that rating. I recommend using the 2 Ohm DVC speaker making 1 Ohm BTL total load seen by the design of the IC amplifier chip for stability even though total it is 1 Ohm for stability and heat reasons. The IC amplifier chip will get very hot running into two 1 Ohm coils since it will look like 1/2 Ohm load to the device and several audio folks don't recommend that low of an impedance to amplifier IC's unless they are designed specifically for this. Examples would be Class D subwoofer amplifiers in the aftermarket world can run into sub 1 Ohm loads and make gobs of stable power. Read my how to post showing how I replaced mine with a Kicker comp speaker available with dual 1 or 2 Ohm voice coils. You will have to trim the small ribs from the inside of the factory sub enclosure for the much larger magnet to fit and seat properly. I ended up totally bypassing the factory amplifier module because it is really in reality only a 30W audio device operating into that load absolute peak power with a hurricane blowing it down hill. I purchased a Kicker amplifier made for ATV's and off-road motorsports that drives the sub much better than the factory weak stocker amp. The amplifier Kicker makes is so small, it fits up under the dash near the radio and is totally up out of harms way, plus it was made for mud & dirt to get on it a little without frying it instantly like other non-marine grade equipment. I am very happy with the results and would do it again because nobody can tell it's not stock so the thieves don't get tempted and no cargo space loss from aftermarket sub enclosures etc.....

Speaker part numbers: 43CWRT672 for the 2 Ohm, 43CWRT671 for the 1 Ohm per voice coil.
Amplifier part numbers: 42PXA300.4 300 Watt 4 channel amplifier, They also make a 2 Channel but I wanted 2 extra channels for the waterproof wake board can speakers mounted on the rear roll bar.

Link here to my post on replacement: LINK
I just replaced my factory sub with the Kicker 43CWRT672. I went ahead and used both pair of connections from the factory amp. It sounds good, but should I have only used one pair and just taped off the other? If so would it improve anything? I plan to get an amp eventually.
 
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I just replaced my factory sub with the Kicker 43CWRT672. I went ahead and used both pair of connections from the factory amp. It sounds good, but should I have only used one pair and just taped off the other? If so would it improve anything? I plan to get an amp eventually.
As long as the connections are wired independently to each voice coil, use both. You will get the most power by using one circuit to one voice coil for both coils. You could also "bridge" the leads and wire the voice coils in parallel, but there would be no point on doing that with this sub/amp combination.

When you buy an aftermarket amplifier for more power, look for the RMS wattage rating at either 1 ohms or 4 ohms. You're looking for something that does about 150 watts RMS at either of those impedances. If the rating is at 4 ohms, wire the voice coils in series. If the rating is at 1 ohm, wire the voice coils in parallel.

Only compare the RMS wattages. Peak ratings generally are meaningless for comparison.

I installed this amplifier: Kenwood KAC-M3001 600W Class D Monoblock Compact Digital Car/ATV/Marine Certified Amplifier https://www.amazon.com/dp/B00U80FUHA/?tag=wranglerorg-20
Since it's rated at 200 watts RMS at 4 ohms, I wired the voice coils in parallel. I liked this amp because it is very small and water resistant, so if it rains I'm not screwed. I mounted it immediately behind the instrument cluster in the dash. Since it's rated at 200 watts RMS versus the 150 of the speaker, you'd just have to be a little bit conservative on the gain dial.
 
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As long as the connections are wired independently to each voice coil, use both. You will get the most power by using one circuit to one voice coil for both coils. You could also "bridge" the leads and wire the voice coils in parallel, but there would be no point on doing that with this sub/amp combination.

When you buy an aftermarket amplifier for more power, look for the RMS wattage rating at either 1 ohms or 4 ohms. You're looking for something that does about 150 watts RMS at either of those impedances. If the rating is at 4 ohms, wire the voice coils in series. If the rating is at 1 ohm, wire the voice coils in parallel.

Only compare the RMS wattages. Peak ratings generally are meaningless for comparison.

I installed this amplifier: Kenwood KAC-M3001 600W Class D Monoblock Compact Digital Car/ATV/Marine Certified Amplifier https://www.amazon.com/dp/B00U80FUHA/?tag=wranglerorg-20
Since it's rated at 200 watts RMS at 4 ohms, I wired the voice coils in parallel. I liked this amp because it is very small and water resistant, so if it rains I'm not screwed. I mounted it immediately behind the instrument cluster in the dash. Since it's rated at 200 watts RMS versus the 150 of the speaker, you'd just have to be a little bit conservative on the gain dial.
Thanks for the quick response. I'm pretty happy with the sound. But may upgrade the amp later on. Thanks again.
 
I just replaced my factory sub with the Kicker 43CWRT672. I went ahead and used both pair of connections from the factory amp. It sounds good, but should I have only used one pair and just taped off the other? If so would it improve anything? I plan to get an amp eventually.

Do you remember what color wires connected to which terminal on the sub? I want to get that same kicker sub wired in with the factory sub but I don't know which color wire goes where.
 
Do you remember what color wires connected to which terminal on the sub? I want to get that same kicker sub wired in with the factory sub but I don't know which color wire goes where.

I am looking into this stuff as well...I see they don't make that sub anymore. They only make 2 ohm and you would lose out on more than half the power from the amp. :(
 
2 ohm DVC, which this Kicker is, you wire in parallel to pull 1 ohm.

How do you wire the factory amp in parallel? Isn't it a two channel amp with each channel going to one of the DVC?

Or it is a mono amp?

Is the OEM speaker 2 ohm dvc or 1 ohm DVC?
 
How do you wire the factory amp in parallel? Isn't it a two channel amp with each channel going to one of the DVC?

Or it is a mono amp?

Is the OEM speaker 2 ohm dvc or 1 ohm DVC?

I do not recall what the specs of the stock speaker and amp are, but per Jerry's first post on this thread, which I believe to be accurate, the speaker is a 2 ohm DVC and how it pulls 1 ohm from the stock amp.

The third way to wire a DVC speaker is by using two amplified channels. Wire one amplified channel to each VC. If the factory amp is one channel, you would then wire in parallel.
 
I do not recall what the specs of the stock speaker and amp are, but per Jerry's first post on this thread, which I believe to be accurate, the speaker is a 2 ohm DVC and how it pulls 1 ohm from the stock amp.

The third way to wire a DVC speaker is by using two amplified channels. Wire one amplified channel to each VC. If the factory amp is one channel, you would then wire in parallel.

Suppose if I hooked up an ohmmeter between two positive speaker outputs on the factory amp, it should be an open circuit if there are two channels and no almost no resistance if it is mono and the wiring is parallel?

Is there a way for me to definitively measure the stock setup for how many ohms the stock sub voice coils are?
 
Suppose if I hooked up an ohmmeter between two positive speaker outputs on the factory amp, it should be an open circuit if there are two channels and no almost no resistance if it is mono and the wiring is parallel?

Is there a way for me to definitively measure the stock setup for how many ohms the stock sub voice coils are?

The stock subs you can use an ohmmeter but it is 1.9 ohms per coil. Here is a picture from another thread. I believe the first post on this thread goes over it. What are you trying to accomplish here?



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