Did anyone figure out this 4 wire switch yet? I'm trying to troubleshoot the dual circuit brake dash warning light system on my deuce. Basically the quick story is that at some point the warning light was removed and the harnesses unplugged. I purchased a new light, and am trying to get the harnesses back in place but not sure to what. My truck (88 m109a3 AF) has the 2 wire push button swith now. So I have this wire harness with 4 plugs as well as a 2 wire (3 pin plug) hanging there not connected to anything . they all loop back into each other and only have 2 wires leaving the harness to go under the truck to the airpacks, proportion valve and ebrake switch.
I know what the individual plugs do on this harness (127 and 167 go to the dash light) What I cant figure out is where do the 4 pin plug (117,118,127,174) and the 3 pin plug but only 2 wires (127,174) go? any help would be appreciated. I'm pretty sure I need to get 127 connected to a +24v supply somewhere, just dont know where? the switching for the warning light seems to come from the ebrake switch and airpack switches going to ground.