W123 Instrument Cluster Mystery: What is this connector?
 

im putting my w123 cluster back in my car and I seem to have grown another connector...theres no obvious place for it in the cluster or around it. its the same type of connector that goes to the back of the speedo.

at least when i took it apart, the speedo electrical connector was red/white and came up near the speedo cable.

this mystery connector is the same type of connector and has brown/green(yellow stripe). it is part of the cluster harness that has the rest of the cluster connections.

anyone know what this is or know of a diagram that will help me out?

thanks,
dd

Tachometer???

hmm i dont think thats it - the other 2 wire connection to the back of the cluster (im assuming its the tach) is a different type of connector...

It looks to me the plug that leads to the cruise control. You should see a connector right on top of where the speedo cable is attached. It is a black male connector.

hmm, the problem is i have two identical connectors to this. the other one (red/white) was connected to the CC on the top of the speedo. is this one (brown/green) the on that should be up there.

i cant tell from the FSM.

Did you look at the electrical diagrams?

yes - but the ones in the FSM doesnt anywhere show the connection to the speedo in the 'gauges' schematic #120. in schematic #111 they talk about a 'vehicle speed sensor'. im assuming this the name for the electrical connection on the back of the speedo and is part of the cruise system.

Correction: the wire that was in my 'vehicle speed sensor' slot is one wire red, the other wire is gray/purple. it comes up from a big run of wires below the ignition switch. it *looks* like it being mis run up to the back of the cluster.

So, it only makes sense that the wire i have pcitured in the first thread IS indeed the wire that should go to the back of the speedo and the wire that *was* in the back of my speedo is the mystery wire.

i have further confirmed this - when i plug the red/grey wire into the speedo my off current consumption on the car goes from 4ma to 18ma. thats not right. when i plug in the other one it is at about 4-6ma. thats right.

so the mystery continues. ill take some more pictures and post them.

thanks for all of the help so far...

Hate to dig up an old thread, but did you ever figure out where the mystery plug goes?

i left the plug that was in the back of the tach disconnected. the 'mystery wire' was indeed the speed sensor for the cruise control.

sort of irrelevant since i have done away with cruise on both of my 300D's :-)

dd