Aftermarket Radio Rear Speakers Dont Work

[Tanzimur]

So on my 98 A4, non bose system i installed a jvc radio and the front speakers only work, i know the rear speakers do have the fancy amp and so forth but my question is how do i wire the left over harness into the functioning/ new harness to make the rear speakers work without buying the harness? Ive looked for right up but none that have current functional pictures so kind of hard to do. Thanks in advance!

[coolgraymemo]

The wiring adapter is about ten dollars on eBay.

Non-Bose don't have a rear amplifier.

[R490]

Check the wiring diagrams.

[Tanzimur]

Ye i know there cheap but want sound like tonight cause im back to work next 5 days... lol and how would be the way to wire it without the harness?

[coolgraymemo]

Google. There's a forum post on wiring it the ghetto way.

Look up pinouts.

[Tanzimur]

dont see any...

[richardodn]

The wiring adapter is about ten dollars on eBay.

Non-Bose don't have a rear amplifier.

That is incorrect for the Avant. The Avant takes power for the fronts at 2x20W off the head unit. It uses the line out pins to a 4x20W amp integrated in the subwoofer. 2 of those channels go to the rear speakers and the other two for the DVC speaker in the sub. Are you sure there isn't an integrated amp in one of the deck speakers that powers the deck and rear doors?

[seanf86]

The wiring adapter is about ten dollars on eBay.

Non-Bose don't have a rear amplifier.

yes it does, its integrated into the drivers rear speaker in non Bose sedans.

Basically what you do on the multi colored plug thats supposed to have high levels from your new deck going to it, you splice the rear speaker outputs from your new deck to those wires, then go in the trunk and butcher the amp on the drivers rear speaker so that those wires are directly connected to the rear speakers and you've just by passed the factory amp, IMO I'd recommend just changing the rear speakers tho. I also advise against doing this and buy the harness and a proper deck with a few sets of pre outs. The only reason I know this is becuase my car came this way when I got it.

[richardodn]

yes it does, its integrated into the drivers rear speaker in non Bose sedans.

Basically what you do on the multi colored plug thats supposed to have high levels from your new deck going to it, you splice the rear speaker outputs from your new deck to those wires, then go in the trunk and butcher the amp on the drivers rear speaker so that those wires are directly connected to the rear speakers and you've just by passed the factory amp, IMO I'd recommend just changing the rear speakers tho. I also advise against doing this and buy the harness and a proper deck with a few sets of pre outs. The only reason I know this is becuase my car came this way when I got it.

Thought so. Are there speakers in the sedan rear doors too? In that case the factory amp is a 4 channel unit similar to what they did in the Avant.

OP, your other option is to use the preouts from the new deck to drive the factory amp. In this case, you'll need to adapt the RCA line out from your head to the chassis harness. I'm pretty sure there are premade adapters but you'll have to do your research.

[Tanzimur]

ye mine does have the amp and so forth an thanks i did end up gettn the harness!

[walky_talky20]

I believe only the Bose cars have speakers in the rear doors. 4 door speakers, 2 tweeters in front, and 2 woofers on the parcel shelf. All are amplified via the trunk-mounted Bose amplifier.

The non-Bose cars just have 2 speakers in the front doors, and 2 rear speakers in the parcel shelf. Fronts are directly driven by the head unit. Rears are driven via an amplifier built-in to the rear left speaker. That amp likes a fairly hot pre-out signal. 4-volts or better.

I'm not as familiar with the avant setup for either configuration.

[richardodn]

At least for '99, the Avant with the base system is running a component pair in the front doors, a coaxial pair in the rear doors and a DVC sub behind the left hand panel in the cargo area. Power for the front speakers is directly from the head unit. The amp for the rest of the speakers is part of the subwoofer unit. I'm guessing its a 4x20W @ 4Ω unit but I've never taken it apart to be sure. There should be 2 channels to drive the rear speakers and 2 channels to drive the DVC sub. Interestingly, the sub is 2x3Ω coils so I'd guess it's really getting somewhere around 2x25-30W into the sub.

The Bose system in the Avant uses the same basic speaker positions. It's still components up front. I think the rear door speakers are only single cones. The amp is once again part of the subwoofer assembly. However in this case the amp is a 4+1 channel setup. Here's a little sales flyer on the B5 Bose system https://www.bose.co.uk/GB/en/Images/...tcm6-68498.pdf