Metra Speaker wiring harness adapters reversed polarity
 

Just bought front and rear speakers from Crutchfield. Got 2 different wiring harness adapters. Metra 72-4500 and 72-1002. Only difference between them, is reversed polarity. Now, i installed the rear sailpanel speakers first, and used the 72-4500 adapter as pr spec. Used a 9v battery on the old OEM speakers just to check if polarity was right. Looked good.

Well, then of to the front speakers. Did the 9v battery check, and this adapter harness (72-1002) with reversed polarity will also have reversed polarity on the front speakers when installed. Seems to me i should have had 72-4500 adapter harness for the front speakers also. I will have to remove the cords from the adapter socket and switch them. Anyone else got different adapters for front and rear speakers ? Any toughts ?

Re: Metra Speaker wiring harness adapters reversed polarity
 

Interesting. I'm using adapters I bought from Crutchfield several years ago and I never thought to check the polarity. Now I'm a bit concerned lol. Crutchfield also sold me a set for the rear and a set for the front which were different P/Ns.

Re: Metra Speaker wiring harness adapters reversed polarity
 

Yeah, i really dont understand why they have a different adapter for the fronts. The connectors is the same on both, just the cords are switched.
Called Crutchfield tech support, but didnt get any real answer other than 72-1002 was listed for the fronts and that was what they always have included (and the 4500 for rears)

Also, Found this spec From the factory. Should be easy for others to verfify the correct polarity.

Front Left (+) = Tan
Front Left (-) = Gray

Front Right (+) = Light Green
Front Left (-) = Dark Green

this also checks out with the 9v battery test, so i ended up switching the cords on the 72-1002 adapter, so its now the same as the 72-4500.

Re: Metra Speaker wiring harness adapters reversed polarity
 

Wow. Thanks for the info!

I wonder what damage having them reversed on the front for several years has caused? Will it overheat the speaker of the amp in the stereo?

Re: Metra Speaker wiring harness adapters reversed polarity
 

If reversed, they will not play at it fullest. The mebran will pull and not push. As long as both speakers, L & R are reversed, Tech support said it was not a big issue. More of an issue if only one is reversed, as they then will be out of phase (one is pulling and one is pushing)

By the way. I installed Pioneer TS-G4645R front speakers and Kenwood KFC-6965S in the rear. No issues with fitment or installation of the speakers them selfs.
Have a newer Pontiac Cd player with EQ installed. Sound is better than the old OEM speakers, but the CD player is a little short on power for sure. I guess i Need an AMP for the speakers to really get that deep base....

Re: Metra Speaker wiring harness adapters reversed polarity
 

does the power antenna work with aftermarket stereos? I'm assuming it does but the head unit i put in my 91 gta is too long.

Re: Metra Speaker wiring harness adapters reversed polarity
 

Typically yes. There's usually a "power antenna" connection. If not, put it on the "remote" wire.

Re: Metra Speaker wiring harness adapters reversed polarity
 

Just used my Crutchfield purchased adapters today, for my front speakers. Polarity was reversed. So glad you posted this. I don't know if I wold have checked this detail or not.

Re: Metra Speaker wiring harness adapters reversed polarity
 

ah ok ... thanks.

Re: Metra Speaker wiring harness adapters reversed polarity
 

Reviving an older thread here, but it's good info.
Anyway, I am about to order some new dash speakers for my 85 T/A through Crutchfield and their site is suggesting the 72-1002, which as per above are the wrong polarity. What did you guys do to modify yours to the right polarity? Were you able to pull the wires out of the connector easily and reverse them?

Re: Metra Speaker wiring harness adapters reversed polarity
 

I just crossed them. Made sure the positive wire in the harness ended up feeding the positive terminal on the speaker, regardless of wire color. Looks a little goofy, but no one other than you will ever know once it's together.

Re: Metra Speaker wiring harness adapters reversed polarity
 

Makes sense.
I thought the connectors on the speaker end were different sizes for positive and negative, no?

Re: Metra Speaker wiring harness adapters reversed polarity
 

Just for poops and giggles, I ran the 72-1002 number through Amazons vehicle fitment guide and it says Does Not Fit my 1991 Camaro.

I also bought front and rear speakers from Crutchfield last year and also got their speaker wiring harnesses. I will now have to pull the dash pad and look into the harness.

Also, If both front and rear plugs are the same then technically, the rear harness (72-4500) should work for the front. If so then its either modify the 72-1002 harness or just buy the 72-4500 for the front AND rear

Re: Metra Speaker wiring harness adapters reversed polarity
 

You mean you guys "buy" adapters? I've always just ripped the terminals off of junk delco speakers and soldered about 3" of the harness supplied with the new speakers to the salvaged connector.

Re: Metra Speaker wiring harness adapters reversed polarity
 

The harness is $7. Its aint worth the time and effort to solder. Ill just pay the $7 and plug in my new speakers.

Re: Metra Speaker wiring harness adapters reversed polarity
 

No harm will be done, but the sound would be lousy because the speakers would be out of phase with each other and cancel each other out.

Re: Metra Speaker wiring harness adapters reversed polarity
 

Gotcha, thanks fro the info! I'm still learning about audio systems.

Re: Metra Speaker wiring harness adapters reversed polarity
 

+1

While I use adapters when I can or when I need to, I've never "bought" one in a package - ever. Always just spliced the proper connector on the end (and polarity was never an issue ! ) ;)


:driving:

Re: Metra Speaker wiring harness adapters reversed polarity
 

Same boat over in my cart on Crutchfield. I suppose I’ll just call and say sub in a second free 4500 over the auto-selected free 1002 for the fronts.

Way to go on this thread fellas!