Let us begin with the circuitry for this lower spec without amplifier.

Radio Less Amplifier
The installation includes the radio with connections C967a, and C967c, the Radio Interface Module (RIM) C529, the radio remote control switch (RCS) (standard after 1/95) C552 and the front and rear speakers connected directly to the radio. If your radio includes an amplifier you will also see the connector C967d on the radio.

The radio connectors are shown here:

Above, the C967a connector. Note that that there are two options, higher and lower content options. I suggest that you will find that it is the 7 pin connector on the right which you will find, particularly if you have the Executive model.

The C967c is shown above. It connects the radio to the RIM

If a third connector is found, the C967d then you should be skipping this part and going onto With Amplifier, because you got one!

There is no need to show the location of the radio - that is obvious. But where is the Radio Interface Module? below is a view of the connections behind the drivers lower fascia, the panel below the steering column. It is easily removed by removing the visible screws and carefully disconnecting the diagnostic multiplug. It is not necessary to detach the bonnet release cable.

The RIM is the unit labelled as A101 and connector C529, which I show below.

It just remains to show the Remote Control Switch (RCS) connector C552 beneath the steering column shroud:

Now, since we know the connectors on the back of the radio, the location of the RIM and the connectors on the units, we can begin to understand the installation.

The RIM receives power through a 5A fuse No 8 in the Central Junction box to Pin 10 on C529. Remaining connections are shown in the following table.
 

You'll note that there is no connection for the Vehicle Speed Sensor in this installation. This signal is used for the Auto Volume Control on higher spec models, and is useful for SatNav installations. Also useful is the detail of the internal connections for the Remote Control Switch (RCS) If you need to connect a different head unit it may be possible to make up your own connections for it.

Next, the installation with the Amplifier.

Radio With Amplifier
As you would expect, the amplifier intercepts the speaker signals from the radio, so the speakers are not connected to the radio at all - this has caused some confusion. Hopefully it will become clearer now.

First, we need to locate the amplifier A13.

The Amplifier A13 is behind the glove box, reached by pushing the glove box stays outward lowering the glove box and removing the lower passenger side fascia. It is connected by C629, shown next:

However, there is a complication. Apart from the speaker outputs and a few others on C629, all connections between the radio and the amplifier are simply shown as Ca and Cc. Pins 1 to 8 on the radio are shown connected to pins 8 to 1 on the amp, but the functions of the wires are not shown. I believe this to be a cable connector, using round din-type multiplugs at both ends.

This need not be a problem. If one is installing a new head unit you wouldn't need to use the amplifier at all, and the power to it can be disconnected. If you are fitting only an amplifier - then there's a problem. Ultimately all that can be done is use the speaker out connections - unless you can test the pins on the amplifier end of the cable connector and find the low-level amp input.

The pins for the Remote Control Unit (RCU) and the Radio Interface Module (RIM) remain the same except that C967c is replaced with C967d.

Connector detail is as follows.

There now remains the Premium Sound System installation.

Premium Sound System

Standard equipment for the Ultima and available as a cost option for others, is the Premium Sound System. This adds a CD autochanger (CDC), mounted in the boot of the saloon or behind the nearside rear luggage trim on the estate. The connector for this is C565.

Otherwise the installation follows the standard practice in the Scorpio. The connections for the CD changer (CDC) are spliced into the connections between the Radio and the RIM. Because the wires from pins 1 and 7 on the CDC are shielded by a grounding pin it would appear that these carry the low level signals.

That's the radio installation for the Scorpio to 9/95. I hope this will be useful for anyone contemplating upgrading their stereo. For myself, I have the Estate with the Premier Sound System, and I see that Ford did not bother with good speakers in the rear - probably too far away. I upgraded mine with a separate amp using hi-level input from the rear speakers, and replaced the fibre things with Pioneer 6 X 9s. Oh, and a Pioneer sub. See Hi Fi for details.