Headlight / Wiper Switches

The metal grounding strap onthe back of the Instrument Panel on 70 Javelin/AMX is not even copper....just put a dash in this past weekend.  It is steel, it is supposed to be attached to the Panel assembly by 2 small plastic pins in the dash casting and then small push clips held it in place during the assembly process.  On 70 this strap continues down to pick up the top, outboard most attachment screw on the "Weather Eye"...Heater-A/C Control Panel.  This method of jumping from headlight switch to wiper to heater control is the reason it is there on every car, regardless of the type of wiper system (electric or vacuum).   If you jam your head under the under the Instrument Panel outboard of the Steering Column you should be able to see the metal plate from the corner of the Heater Control.  I totally agree with George on the other aspects he is describing, the black wire on back of headlight switch is just a ground...nothing more, and originates from the main harness.  The brown wire for power to the Wiper Switch also comes from main harness.  The single black wire for washer pump is just that a single wire from pump to switch, with it's own grommet in the firewall corner plate.  

I am going to try and update on these issues as I still need some help with them. For simplicity sake I will only update on the wiper problem here. I will start a new thread for the blinker / headlight issue which has become more critical to me.

First let me start by saying that this is my first AMC so please don't assume I know anything about them. I have checked the backside of the dash where the switches mount and there is no sign of any common ground strip. Nothing I can see to indicate there ever was one there. Here is a picture of the dash in that location. Does this appear correct?


This is also a picture of the wiper switch which I have come to believe is not OEM and not correct for the car? It has 7 terminals instead of 6 and they are laid out differently than the TSM book shows.



As noted above I got the wipers working by reattaching the black ground wire that had come off but the switch only works on slow speed and does not park when turned off. Tracing wires I found that I really only have a red, black and brown wire to the switch. I thought I was just missing the yellow wire (which I still cant find) but I also found that the blue wire is cut and open in the engine bay so no blue or yellow. I think at this point rather than to tear the main harness apart looking for or running two new blue / yellow wires I may just settle for slow speed only with no park...

A note about the "black" wires. The black washer pump wire should have no bearing on the operation of the wiper motor and is NOT part of the main wiring harness. The black ground wire that connects to the tab on the headlight switch IS part of the main harness.

The wipers are electric. Here is a pic of the motor. I exposed the  wires to show all four coming out of the motor. They go into that pigtail and then disappear into the main harness. On the other end of the main harness a bundle emerges with just the black, red and blue wires that goes through the firewall to the switch. As I noted earlier the blue wire is also disconnected at the harness so effectively just the red and black go to the switch. I suppose if I had the correct switch or knew how this one was set up, I could run two new wires from the blue and yellow at the motor up to the switch and have full function.

401Matcoupe, if you happen to recognize this switch and know how its supposed to be wired let me know. The number on it is very difficult to read but looks like 36512 and to the right of it is 12DB. You are also correct that the illuminating lamp is gone! I am guessing that these plugged into that three prong female plug the my heater lamp is plugged into?



Edited by Bandana - Apr/02/2017 at 11:43am

I have this one Rod,