you may have had an amp interface harness, did it have a box that the wires went through? or rca jacks on the plug?, or was it just speaker wires attached to a female plug? If it sounds very loud at low volume it is most likely wired wrong but I think you would know if this was the case, it usually sounds distorted at medium volumes, I also dont think your factory amp would last very long if you were pumping high wattage inputs into it. I am not entirely sure about some of the newer systems in these vehicles as I have not done alot of work with them, however I know that at some point Ford bought out Jaguar (and LR) and some of Fords premium sound systems will take a high level input (the factory amps have a built in line level converter) I am not 100% sure but i think even the factory Alpine systems on Lincolns are that way. could be the case for you but I would have to see it to tell you for sure. I did see you mentioned using your multimeter I would be curious to know what kind of resistance you are reading between the + and - of the speaker wires on the factory radio harness (without the aftermarket radio harness plugged in)

 

Well, it powered on and have functionality. However, as feared, no sound. Chris, how do I bypass the amp?

 

Crutchfield sent a Volkswagen/Audi wiring harness/adapter. Basically, a block to accept the gray and brown (C0092 and C0098) ISO connectors. I used the instructions to mate the wires coming from the block to the wires coming out of the dash. No RCA connectors were included.

 

find the amp, I believe under the drivers seat in left hand drive vehicles (it will look like a small aftermarket amp with cooling fins on it), unplug all the plugs in it (be sure it is the amp before you unplug anything, I would try to match up a few wires from the harness behind the deck) then you need to determine which wires are speaker outputs, there should be 4 sets and they should be in "twisted pairs" (these will most likely be the majority of the thicker wires) you may want to pull a door speaker out to check the wire colors behind it (they should match a twisted pair). do not cut these wires just tap into each 1 of them with a new set of speaker wires and run these wires up behind the deck, once you have 4 sets of + and - speaker wires behind the deck you can put a AA battery between the + and - leads of each speaker wire to "pop" the speaker to determine which wire goes to which speaker (only use the AA battery if you are certain these are connected to the correct wires)

 

sinebubble how many plugs were in the back of the radio? just those 2 or was there a 3rd longer one as well?

 

Sorry Chris, but which radio? The R990 has three blocks and two coaxial like connectors (I assume these are the antenna). The X100 has six RCA (front/rear/sub) and a grip of wires.

The "Scosche Ford/JBL and GM/Bose Speaker Level Converter, FAI-3" line leveler should work for the Disco?

 

the scosche unit you will need is slc4,it is a blue box(looks exactly the same as the one you are asking about but it is a multi-purpose converter)I am not sure if this one will work. it will allow the adding of an aftermarket deck to a factory amp (which is your purpose) and it will allow you to add an aftermarket amp to a factory deck. it should have 4 channels in and 4 channels out as well as 4 rca outputs which you should not need.

http://www.crutchfield.com/p_142SLC4...4.html?tp=2001

 

what is connected to pin 5 on C0098 the gray connector?

 

Pin 5? Nothing. I pulled this from another site discussing a similar issue.


C0098 (grey connector)
1 .......Telephone mute Input
2 SB ...Steering wheel remote radio controls Input
3 SR ...Steering wheel remote radio controls Output
4 P .....Permanent battery feed Input
5 RU ...System enable Output
6 RN ...Illumination Input
7 LGP ..Auxilary feed Input
8 B ......Earth Input

Pins 2 and 3 of the grey connector you will probably not use, and pin 5 turns on the factory amp, which again uses "high" level inputs and will likely not work with your new headunit as that will "probably" have low level RCA outputs.

 

pin 5 has to be connected to the Alpine blue\white wire, if there is nothing in that slot for the crutchfield harness, but a red/blue wire on the factory plug (where that wire should go) try tapping your alpine amp turn on wire to that. If you hear sound and it is very loud you will either need to get that scosche box to wire in between the alpine harness speaker wires and the crutchfield harness speaker wires or get a new amp integration harness metra part number 70-1786