70 LT1 Door Ajar electrical gremlin

[Terry M.]

Re: 70 LT1 Door Ajar electrical gremlin

I know one wire was for the alarm in 73 so you only need two wires with no alarm. one is the ground the other lights the door adjar light.

You nailed it Lyle. The "extra" wire in 1968 to 1971 is for the optional UA6 alarm. In 1972 that alarm system became standard equipment.

[William G.]

Re: 70 LT1 Door Ajar electrical gremlin

Looking at the 70 and 71 schematics in the AIMs it is clear that the door ajar switches are pass-through switches that complete the door ajar circuit when either or both doors are open and the key is supplying 12v. My 70 has a black and light blue wire coming through the car into the cavity in front of the access cover and then out through the door jamb to the switch.Same on both sides. According to the AIMs the ground is further on down the line via the black wire. So there is no ground needed to the steel switch plate on my 70 without alarm. My problem must be further along the line and I will have to chase it down. Thanks to all for your help. Bill Gould