Aftermarket Stereo Upgrade Help

[Chris Potts]

Hi

I have a 1998 GS300. The current stereo has a damaged screen , so decided to go for a kenwood unit with dvd, built in sat nav etc.The garage has tried to fit today but gave uo due to the amp in the car. Is it possible to connect an aftermarket system with the existing amp and speaker connection. He has quoted 300 quid for an additional amp with a already expensive system. He managed to get a hold of a link harness for the vehicle harness to connect to the new unit, but said there is not an additonal harness available to connect up the amp ?. If it is possible does anyone have a wiring diagram or give advice on how to connect up to the amp, with a existing harness or a made up harness

Thanks Chris

[TigerFish]

I am about to go through this process on my '99 Sport. The two options I am considering are:

1. Use the RCA outputs of the head unit and feed those to the existing amp. No idea if it'll work or not.

2. Do what I did on my '96 Sport, and bypass the amp. I did it at the amp location before, disconnecting the amp and joining the inputs to the outputs on the connectors. Just saved running new wires to the speakers.

Does your new head unit not have a built in amp? If it does, in simplest terms, and cheapest, the garage should just be able to run new speaker cables to the speakers. Have they not suggested that?

[Chris Potts]

Hi

The new unit must have a build in amp but he stated that the sound quality would not be as good due to the existing amp quality. The bass would be poor also.

That put me off a little to pay £900 for a v good unit without have the current sound quality.

There shouldn't be a reason why the current amp can't be wired if there is any wiring info available?

[TigerFish]

Diagrams below. For what its worth, the sound quality improved (IMO) when I ditched the factory amp in my Mk1. Although I never ran the factory sub with my new head unit, I had a Vibe active sub in the boot, but the bass was really good even with the sub turned off. I'll have to wait and see how it goes with the mk2.

[Chris Potts]

Thanks for that hopefully this should help. Did you manage to wire up all yours speakers including your sub?

Also on the diagram what is the navigation ecu connector for , an upgrade ?

One last question , do you know what the power inputs and outputs are for the amp, as the garage said he could try and connect the new stereo to the old amp but didn't want to blow it

Thanks

[TigerFish]

The navigation ecu will just be the factory sat nav connector to feed the instructions through the speakers. If your car is non sat nav, it is not practical to swap the factory units.

No idea on the power inputs and outputs of the factory amp.

I was running my Vibe sub with the aftermarket head unit. The rest of the speakers were running fine (excluding the factory sub, which I removed).