The brown wire to the rear bulb in the console is the ground wire. I meant to say that the female connectors to that bulb may need to be squeezed a little to keep the small male prongs in place.

There are several ground wires in the bundles under the center console. They are easy to spot, they all get attached to the wall of the tunnel. Most are brown in color. The grounds are normally OK, unless there is a large amount of coffee or cola that seeped into the area. Same for the switches. Sometimes, a sticky switch, probably not your case, can be cleaned just by moveing it back and forth a dozen or so times.

When I first got my 854T, there was a phone cradle in the car. One of the wires was connected to the same fuse as the mirror switches. When I removed the phone power wire, the fuse was loose and would only make contact when it felt like it. I bent the bottom prongs of the fuse and now all is well.

As for the defrost, save that for last. Yes the mirror comes off, but you need to be able to tilt the glass to pop it off and check the wires. Then you can use a multimeter to check for voltage when the defrost switch is on. It could even be a broken wire at the door hinge.

Klaus

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The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)