subwoofer not working correct.

[bmann 12]

when i turn my key on (with the car running or not) my subwoofer just beats like a heart constantly. anyone ever have that problem? iv tried two diferent amps both do it, i have checked the ground and power wire, checked the remote connection, run the Aux cables opposite side of the power wire, 1.5ft long ground cable. and when i have regular speakers hooked to the amp they have a high pitch screaching noise and as i hit the gas the screachign gets lounder. any ideas?

[Swbari00]

Sounds like you have some grounding issues somewhere. Unhook all RCA cables from all amps and see if you still have those problems.

EDIT: Make sure you have everything turned OFF when you unhook stuff!!!

[bmann 12]

i tried that and it does not do it when rcas are out of amp? thanks for imput any other ideas?

[Walt]

When did this start? I agree you've got a grounding problem, but its a vehicle wide issue...

[bmann 12]

it just randomly started. i had my woofer in and it was working just fine for couple months. then just one day going down the road it started thumping like a heartbeat i have no clue what happend

[Swbari00]

What kind of radio do you have?

[bmann 12]

kennwood KDC-138, its about 6months old


i have 2friends with the same truck with the same headunit with subs and theirs both work great.

[Swbari00]

do you just have a single amp? mids and highs running off the radio power?

Did you make a new ground for your radio or simply use the ground on the wiring harness?

Does it do it no matter what source your are using? (ie. radio, CD, AUX input)

[bmann 12]

i have a single amp. and i have the ground just from the harness. and yes it does it no matter what source im on.
how should i go about makeing a new ground for the h/u??
thanks for the help

[Swbari00]

To make a new ground for your h/u, do it the same way you did for your amp. Find a good metal spot that you know is part of the chassis (test with a DMM) and ground it there. Unhook the ground from the harness and just use the new ground.

This may not fix the problem, but it is something that should be done anyway.

Are you certain the RCA cables you are using are good? If your new ground doesn't fix it, that would be the next thing I check.

[bmann 12]

alright i will ground my h/u later today and see if that works. otherwise i guess ill have to try new rca cables
ill let you know what happens

[bmann 12]

re grounded the headunit. still does the same thing. ill have to ask around to see if any of my friends have any RCA cables i could try. i sure hope i can figure this mess out. i might just try a new deck. i have an old one sitting around. maybe its the Rca ports on the headunit?

[killian96ss]

If everything worked before and now this problem popped up, I would say try a different stereo. I have Kenwood stereos in all 3 of my vehicles and really like them, but I have had a few new stereos fail or do weird things like yours in a short amount of time. Last year I replaced an older Excelon In my SS because it was turning the volume up and down by itself!

Steve

[bmann 12]

are u sure the turning up and down wasent that control where the volume is judged by the engine? and yeah i love my kennwood but i got an older alpine just sitting here i guess ill try that maybe tomorrow and see what she does.

[Swbari00]

It could very well be the radio, it is usually just easier to check other things before swapping out a h/u.

[bmann 12]

yeah i agree but iv tried everything. its come down to it i guess its my last option
lol

[bmann 12]

and that did not work. guess my brother fried it and didnt tell me :/ guess ill ask around to find a different one

[killian96ss]

are u sure the turning up and down wasent that control where the volume is judged by the engine?

Some of the factory stereos do that, but this one didn't have that option, it was possessed! Do you know anybody with an old stereo you can try out?

Steve

[bmann 12]

no i been asking around but cant find any. im also still trying to find other RCA cables maybe mine went bad. but everyone is using theirs :/

[Swbari00]

just go get a cheap pair from walmart or radio shack. they will work well enough to tell you if your other pair is bad.

[bmann 12]

looks like that is what im going to have to do..

[bmann 12]

tried new RCA cables and still wasent the problem.. gunna have to find a H/U
where do you all have yours grounded?

[killian96ss]

The last 10 or so stereos I've installed were plugged into the factory harness and none of them ever had grounding issues. The stereos I've manually grounded were in older cars, and I always used the closest common ground available which also never failed. I don't see why you would need to manually ground the h/u in your CC, unless you are for sure having grounding issues which would be obvious.

Steve

[killian96ss]

kennwood KDC-138, its about 6months old

Is it still under warranty?

Steve

[bmann 12]

i mean where do you ground the amp. and i cant find the reciete!

[killian96ss]

i mean where do you ground the amp. and i cant find the reciete!

The amp ground wire should be as short as possible. All of my amps are grounded to the body either in the trunk or just any convenient spot where you can drill a hole for a screw. I always try to use an existing ground when possible. The most important thing is to make sure the ground wire is attached to clean bare metal. Scrape off any paint and put a little dialectic grease on the metal before you screw down the ground. This will prevent any rust from ruining your good ground. If you ever get any humming or buzzing out of your amp try another ground on the opposite side of the vehicle. Some of the cheaper amps are a little picky.

If you Kenwood h/u is a newer model Kenwood might fix it for free or maybe for a small fee.

Steve

[bmann 12]

i tried the switching ground sides but it didnt work either. still gotta be the H/U

[Walt]

Have you tried adding an additional ground to the battery? Its a long shot, but might be worth it.

Sent from my HTC Desire CDMA using Tapatalk

[bmann 12]

what do you mean?

[Swbari00]

He means add a second grounding wire to your battery under your hood. Although my guess is still on it being a h/u problem.

[Walt]

This doesn't help you, but some vehicles just have a noisy electrical system... alot of Fords in the early 2000's had this problem...

Sent from my HTC Desire CDMA using Tapatalk

[bmann 12]

well one of my buddies with the same h/u as me finlaly gave in and let me borrow it to see if mine was bad. i hooked everything up and it worked like a charm. looks like ill being taking this one back hopefully its under warenty. otherwise stock radio going back in

[Swbari00]

glad to hear it man. That was my sneaking suspicion but it is always good to make sure everything else is working too.

[bmann 12]

yeah, thanks for all the help though! i appreciate it!