MyE28.com

Hi,

I’m in the process of repairing the harness and reinstating an oem pioneer KE-81 zeM-02 in our e28 M5. I’ve figured out all of the power, ground, antenna/amp leads. What I’m unsure of is the speaker connections at the radio.

Right now there is a single yellow lead and single blue lead. I understand this is for left and right and the speakers use a common ground. The factory connector at the radio for each of those has a spade and pin.

My question is this. I’ve found 2 versions of this connector, one with 2 wires and one with one. I think the premium sound e28s use the single wire version. Which terminal does the wire get connected to? The spade or the pin or are they jumpered in the connector?

I can provide pictures if it would help.

Probably not much help, but there's a listing for one of these radios on eBay with a pic of the rear panel showing stubbed off wires so you can kind of see what goes where:

https://www.ebay.com/itm/276602524540?_ ... 6ZA&edge=0

Looks like you should have four wires, yellow/yellow-brown and blue/blue-brown.

Thank you for posting that! I actually found that one as well. I believe that radio is out of an e30 as it has 2 wire speaker connectors and a back mounting pin.

I get what you're saying now about the premium sound setup just having single-wire connectors. There wouldn't be a second pair of wires until you get downstream of the thumbwheel fader control which divides the signal into front and rear IIRC. Before that, as it comes out of the radio, it would just be left and right. And the L and R would literally be single wires thanks to that oddball common chassis ground arrangement they used. I converted my premium sound car to standard wiring several years ago and in fact did a small writeup about it (it's one of the posts on Shagrath's excellent sound system rewiring thread). Unfortunately I can't remember details about how the connectors' pin and spade were wired. It seems possible they'd be internally jumpered as you speculated. Have you tried testing for continuity between them?

I haven’t but I am going to. I’m also going to check them for continuity to radio chassis ground. Would you happen to have the plugs from when you upgraded your radio? I’m hoping to just find a set and wire them up.

No unfortunately I don't have those anymore.

I did find this, though:

https://www.ebay.com/itm/296213127172?_ ... 7ZA&edge=0

Another eBay radio but this time very possibly from a premium sound E28. There's a good pic of the connectors, which have single yellow and blue wires. Might be enough clues to tell whether the wires attach to the spade or pin side.

Screen shot for archival reference purposes: