For anyone who's thinking about replacing their stock head unit (HU), the new HU with the appropriate ISO adaptor and aerial adaptor will most likely not activate the rear amp to power the rear speakers. This is because the connection to activate the rear amp from the new HU will not be in place resulting in the rear speakers not working. Either find out how to activate the amp and have the signal from the new HU amplified, again, by rear amp before it reaches the rear speakers or introduce new wires connecting directly to the rear speakers.
However, I've found another way of bypassing the rear amp without having to route new speaker wires to the rear speakers.
If you want to do this, you need to disconnect the plastic connector to the rear amp and connect the wires as shown in the image below. For these connections I cut up wires from inside a disuse telephone socket as these are rigid but yet maleable enough for the job. These wires have an outer plastic lining required to stop likely short circuits in this application. You need to strip back approx. 5mm of the cover from both ends of the wire of appropriate length, bend half the bare part back forming a V on both ends and insert into the correct connector sockets.
After inserting all four wires, use duct tape to keep these links in place-just in case it should come loose. There may be thicker wires which are more appropriate for the job if you have time to source them out.
I hope this will be of use for people who do not want to mess around looking for possible wire routes and do not want to use the existing rear amp.
For anyone who's thinking about replacing their stock head unit (HU), the new HU with the appropriate ISO adaptor and aerial adaptor will most likely not activate the rear amp to power the rear speakers. This is because the connection to activate the rear amp from the new HU will not be in place resulting in the rear speakers not working. Either find out how to activate the amp and have the signal from the new HU amplified, again, by rear amp before it reaches the rear speakers or introduce new wires connecting directly to the rear speakers.
However, I've found another way of bypassing the rear amp without having to route new speaker wires to the rear speakers.
If you want to do this, you need to disconnect the plastic connector to the rear amp and connect the wires as shown in the image below. For these connections I cut up wires from inside a disuse telephone socket as these are rigid but yet maleable enough for the job. These wires have an outer plastic lining required to stop likely short circuits in this application. You need to strip back approx. 5mm of the cover from both ends of the wire of appropriate length, bend half the bare part back forming a V on both ends and insert into the correct connector sockets.
After inserting all four wires, use duct tape to keep these links in place-just in case it should come loose. There may be thicker wires which are more appropriate for the job if you have time to source them out.
I hope this will be of use for people who do not want to mess around looking for possible wire routes and do not want to use the existing rear amp.
Van