NissanDan

I recently inherited a 2002 Nissan Maxima from my grandfather who passed. The head unit turns on and everything works (except for the tape deck) but there is no sound. From my understanding and the search I've done on this forum, there is an amp in the trunk for the speakers, but I can't seem to find it anywhere. Does anyone have any pictures they can provide?

I suspect that the issue is with the amp, perhaps the amp died or a fuse blew or it got disconnected?

I'm planning on replacing the head unit with a double din that has a screen for a backup camera and which will have 4V preouts to connect to this Bose amp. If the amp is kaput, I can try replacing it first. Will it matter what amp I use in this case or should I replace with the original?

Thank you in advance for any help you can give.

Prophecy99

iTrader: (1)

just replace the headunit and see where it goes. the amp in the trunk is just for the subwoofer. i recommend crutchfield as they are extremely helpful and help you more than you might think. they will give you everything you need to swap the bose out.

NissanDan

Aren't there amps for each speaker then? If so, from my understanding, I need to get a wiring harness that converts the RCA preouts into the harness and it still doesn't mean that one or all of the amps didn't go bust. If not, then I want to get a powered head unit if it was getting power from the head unit. This is why I need to know if I need to go with a powered head unit or with one that has preouts to connect to the amps of the speakers.

Prophecy99

iTrader: (1)

crutchfield should be able to help you with all that. (i don't work for them), but they helped me over the phone in the middle of my bose swap out. I didn't have speaker issues like you but talk to them they will be helpful.

or look around here more, theres plenty of info around here already posted.

ajahearn

iTrader: (3)

I can send you my old HU if you want (we can talk about shipping costs) but it hasn't been in the car since 2014. I would go with another HU because there are so many better options now.

CMax03

iTrader: (3)

Go aftermarket....It's got more features like Bluetooth, phone jack, USB ports etc....

Prophecy99

iTrader: (1)

yea i cant believe i waited so long to replace mine, completely updated my car with all those features and made it feel like a newer car, hands free calling, and the BT audio and way better audio controls etc.

NissanDan

According to crutchfield:

Hardwired connection to parking brake required
The wiring harness does not have a ground connection, so you'll need to connect your new car stereo to a grounding point in your vehicle.
In order to retain the factory amp, the wiring harness in this package connects to your new receiver's front and rear preamp outputs. If you've chosen a receiver without those outputs, our installation package will include the line converter you'll need to retain use of the amp.
You'll need to use the factory radio's brackets in order to install your new receiver. If you don't have the brackets, you can obtain them from your dealership.
In order to retain the factory amp, the wiring harness in this package connects to your new receiver's front and rear preamp outputs. If you've chosen a receiver with an output voltage below 4 volts our installation package will include the line converter you'll need to retain use of the amp.
If you plan to bypass the factory amp, we recommend replacing your vehicle's low-impedance speakers with standard 4-ohm aftermarket speakers to avoid damaging your new radio. If you want to keep your factory speakers, you'll need to add an aftermarket amplifier.

See in bold - it looks like there are amps for the speakers according to them? And they don't suggest using a receiver's amp since it can damage the new radio? If there are amps - could the amps be the problem in that case? Where are they located?

Prophecy99

iTrader: (1)

have you not purchased anything yet? if you plan on replacing, go thru crutchfield and they will certainly give you everything you need including the convertor to use the factory amp, then you can tell them about your concern with the existing amps functionality, and as an option to eliminate that problem if you can get a new amp to work with the new set up instead of a convertor to the original bose amp.

it sounds like you are trying to diagnose the amp problem before doing anything....which is fair, but maybe just swap it out at this point. i don't remember where the amp was honestly, someone may be able to chime in, i can safely guess you need to rip out the head unit to get to it, and that point.... you should have a new headunit and if you suspect the amp, just swap it out instead testing it w a new set up, and opening it all back up multiple times.

I didn't have to replace my factory amp because I had sound before the Headunit replacement, and just used the convertor they provided.

slvr2KSE5

The speaker amp in your Bose system is in the head unit. Amp in rear is only for the sub. Earlier years did have a separate amp for the speakers

Prophecy99

iTrader: (1)

thanks for chiming in, i couldn't remember if there was an amp, i just remember the unique set up of the factory bose, and when replacing it requires a convertor to use the factory speakers.

Computernaut

I had the same issue (head-unit working, but no sound) and it was just the audio fuse (which is in the engine compartment fuse box...for some reason). May as well check that first so you don't have to go on a wild goose chase (like I did).

nick

iTrader: (10)

The subwoofer on the 2003 I35 has its own amp. It's in the plastic enclosure under the factory subwoofer.

The stock BOSE amp that powers 4 door speakers it's under the rear shelf on the right side, it's a black rectangle with Bose logo on it.

I recently installed an aftermarket Kenwood head unit with 5V pre-outs and used the recommended Metra 70-7551 harness (with 4 RCA pre-outs) and the sound was weak and very shallow. Switched the harness to Metra 70-7550 and it sound much better. Eventually going to replace the door speakers and install a proper 4 channel amplifier, but it sounds fine for now.