Hi All,
Just bought a CR-814(6 speaker external amp) to replace the CR-718 (4 speaker no amp) on ebay for my 740 turbo and have two questions before I install:
a.) Do I need the 6 pin din cable and the rectangular connector on the amp? I'm confused on what I found in the archives because it sounded like I only needed the din. If I need the rectangular one I'm confused on where the other end is going because the one off the back on the radio goes to speakers,power, etc.
b.) Any chance all the wiring and cable ends will be already in place and ready to go for the amp?
Thanks in advance,
Robb McC

I'll preface this by saying that most of what I've done in 740s is in pre-90 cars but that the basics are similar. The 700/900 FAQ will hopefully help even more.

The 6 pin DIN is speaker channel inputs to the amp.
The 9=pin rectangulars go like this:
The car's harness has a basic stereo plug. This has power, switched power, ground, 4 wires for 2 front speakers, power antenna, and a lamp dimmer wire. Main power ought to be from fuse 5, BTW. (Shared with the dome light circuit).

The amp is added into the harness. The amp has one plug that goes into the car's main harness connector to pick up power. That's then split into wires that go into the amp (no other removable connector) and a female plug that the stereo head unit plugs into. So basically the amp wiring goes between main harness and head unit. The amp's outputs for front speakers go back into that original 9-pin plug. The rear speakers are powered through a separate 9-pin plug, into the optional rear speaker wiring harness. For US cars, every one I've seen came with the rear speakers so everything ought to be in place.

I've mainly been involved in removing unhappy factory amps and head units and replacing them with upgraded equipment- the simplest way seems to be to cut plugs off the old amp and splice the new unit to those existing speaker outputs.

I never did break down the wiring of the 6 pin DIN, and if it's all factory stuff you shouldn't have to try to figure that out either.
Best of luck with it.
--
Rob Bareiss, New London CT ::: '87 244DL/M47- 230K, 88 744GLE- 220K, 82 245T-181K Also responsible for the care and feeding of: 88 745GLE, 231K, 87 244DL, 239K, 94 855GLT 189K

Thanks alot - that's enough info that if I have to do any slicing I'll be well armed. What I have is a wagon with factory CR-718 with speakers in rear doors and front dash. In the front doors are grills and wiring but no speakers and no signal in the wires. So I am hoping that the fact that the wiring is there in the doors means that the amp wiring is in place and it will be plug and play and then onto a bike ride Sat. afternoon rather than tracing and splicing all day.
Robb McC