Door ajar circuit gremlin Help Please
Thread Starter
Racer
Joined: Feb 2008
Posts: 383
Likes: 12
From: Plymouth Massachusetts
Door ajar circuit gremlin Help Please
I am finishing up the restoration of a 70 LT1 and am addressing some electrical gremlins. The courtesy light and horn buzzer system is fixed and.Now I could use some help on the door ajar circuit. I installed new switches in each rear door jamb.Each had two wires and the installation went smoothly. The door ajar lamp is supposed to light when either or both doors are open and the ignition key is on. In that condition I get NO light until I pull on the light switch and then I get a continuous door ajar warning light regardless of door or key position. Any ideas as to what is wrong here? Thanks for any help. Bill Gould
Melting Slicks
Joined: Oct 2003
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From: Chapel Hill NC
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A dash gauge light stuck in door ajar socket?
Melting Slicks
Joined: Feb 2018
Posts: 2,325
Likes: 721
From: Marietta GA
The rear door switches on my 73 convertible has three wires. I gonna say one is for the alarm, maybe. Ask me how I remember, the little metal connectors are HELL to get on the switch, so they will always make contact when the door its open. You should check the service manual interior wiring schematic to be sureabout three wires. Also I had to put a rubber bumper on the door to ensure the switch is pushed in when the door is shut.
Burning Brakes
Joined: Nov 2006
Posts: 893
Likes: 7
From: Orange Park Florida
I pulled the switches, removed the multiple wires from the switch and grouped them together. I then attached a single wire at that point and connected it to the switch.
All three wires are common, so now I just have one wire connected to the switch and it is much easier to connect and install into the door jamb,,,
The door provides the ground...
All three wires are common, so now I just have one wire connected to the switch and it is much easier to connect and install into the door jamb,,,
The door provides the ground...
Last edited by JimT; Feb 16, 2019 at 09:06 AM.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,117
From: Crossville TN
The 'Door Ajar' switches connect electrical ground to the [already powered] bulb in the dash. They are wired in parallel so that either one will light the bulb if the door is opened. That arrangement is 'finickey'....switches are cheap and can corrode, wiring is flimsy and can break, etc. etc. There are a million sizes of those switches at auto parts stores; but you need the correct length of switch and plunger for them to operate correctly. The rubber bumper was used to keep the paint from being scratched off by the plunger pin. If the rubber bumper is not used, a longer switch needs to be installed. Simple design; lots of potential failure points.
