12 volt electrical problem 92 imperial

mmcl26554 · 10-10-2011, 11:36 AM

We have not driven our MH at night and only once in rain where I turned the headlights on. It was then I noticed when I turned the lights on the reading on the meters, engine temp, transmission temp, went up and volt meter went down.

Obviously there is a voltage drop, however finding it is the problem and why I am posting. There must be a common main feed junction which both the ignition switch and headlight connect.

I have checked the feed circuit board under the hood but there is no significant voltage drop on any of the binding posts there when the headlights are turned. I also found another series of 4 binding posts on the inside of the fire wall but that was not it.

There must be another junction binding posts on the inside of the firewall which I have not yet found. Unless someone can point me in the direction of where this junction is I will have to trace the main headlight feed wire (black with orange strip) to it. To do this I will have to take apart a lot of the wiring harness which I would like to avoid.

So if some one has any experience with the 12 volt wiring harness and could point me in the right direction it would be helpful. A wiring diagram would also be helpful, but I have not been able to get ahold of one.
Michael

Jimmy F · 10-10-2011, 07:18 PM

mmcl26554

I would look at the grounding terminal bars in the back of the dash. It seems Monaco never really supplied sufficient grounding in these older coaches.

There should be two terminal bars that all the ground leads from the instrumentation go to. Each has a wire from the end of the bar going through the firewall bolted to the chassis frame. Myself, and other who have had this problem, ran another heavy wire from each bar through the firewall and bolted it to the frame . Not in the same spot as the first wire, that way you have increased the ground from the dash to the frame 2X.

For us...this eliminated the problem you describe.

Jimmy

mmcl26554 · 10-10-2011, 08:31 PM

Jimmy,
I do remember seeing a ground lug about straight ahead of the gas pedal, where might I find the other in reference to this one?
Since I have your attention, there is another power feed problem. The power feed to the HR fuse panel (labeled chassis power) on the outer wall left of the steering column which supplies hot at all times power to the radio suddenly stopped working (light green wire). I fixed it for now by jumping in from another power feed. I would like to trace this wire to it's source any ideas where that may be?

Jimmy F · 10-10-2011, 08:54 PM

mmcl26554

Well...I'm not sure. We are now going to get into the specific differences between a 92 imperial and a 95 Dynasty. On mine there are two ground terminal bars behind the dash high up on the firewall on the left side. There are probably, I guess, 20 ground wires going to them so it's lots, not just a few.

The green wire... again, sorry can't help you with that one other than to say it must come from a 12V source somewhere. Perhaps another fuse panel or perhaps directly from the battery. You could do what I did when I ran into this problem for the first time, I bought one of these Gardner Bender GET-4110K Ener Wire Tone Tracer

Mine has helped me lots when trying to find out "where the heck does THAT wires go".

Hopefully there is someone else here with, or has owned, the same coach as yours that has a wiring diagram or know where that power feeds from.

Jimmy