1970 Door Ajar Warning

[Midlife 801]

In 1970, Ford introduced a door ajar functionality in the Mustang.  With a third wire in the driver's side door and a relay, a black wire goes to the turn signal switch (which doesn't make a lot of sense to me).  Later, they added a RUN-only wire to the relay as well.

My question is: what happens when the engine is running and you open the driver's side door?  It's something in the turn signal switch area, but for the life of me, I can't figure it out.

Thanks in advance.

[Ridge Runner 1,056]

If my door is a jar ,i hope it is filled with jalapino stuffed olives ,i like jars of olives !

[RPM 1,157]

Midlife has a Mustang wiring question? Is it April 1st?

[69RavenConv 283]

Can you post a schematic? We all know Ford loved to run every circuit in the car through the turn signal switch, so that part doesn't surprise me. Wild guess is that run-only means the circuit is energized only when the ignition switch is in run, so you'd only get the warning light when the engine running, not in accessory (or off, of course)

On the other hand, I may have no idea what I'm talking about.

[Midlife 801]

Well, apparently there is a key reminder buzzer in the steering column that the turn signal switch attaches to.  I finally found the proper schematic for it.

[Mach1 Driver 528]

Would you like to share?

[aslanefe 320]

5 hours ago, Midlife said:

Well, apparently there is a key reminder buzzer in the steering column that the turn signal switch attaches to.  I finally found the proper schematic for it.

Randy, the key buzzer switch is attached to the column, not to the turn signal switch. As far as I remember, that switch and switches on the A pillars for the interior light to come on when the door is open is in the circuit to activate the key on ignition and engine not running buzzer.

The door ajar light is activated by the switches that are on the door latches, if the latch is not on second catch and door is not fully closed, the light comes on.

I have a dissassembled 70 XR7 with door ajar light and key buzzer if you need more info.

[Midlife 801]

Aslanefe: you are correct: the buzzer is in the column, but the wiring comes through the turn signal switch itself. 

Mach1Driver: it's on the page titled 1970 Mustang Key Warning Buzzer (near the end) of the 1970 Mustang Wiring Diagram Manual.

 

Next Question: do electrons go from + to - or from - to +?  Bonus points for knowing the true answer!

[jmlay 76]

- to +

[69NC 21]

In physics it's the holes that migrate, not the electrons. It makes the math simpler

[Midlife 801]

9 hours ago, 69NC said:

In physics it's the holes that migrate, not the electrons. It makes the math simpler

Ding Ding Ding!  We have a winner!

[Rich Ackermann 172]

13 hours ago, Midlife said:

Aslanefe: you are correct: the buzzer is in the column, but the wiring comes through the turn signal switch itself. 

Mach1Driver: it's on the page titled 1970 Mustang Key Warning Buzzer (near the end) of the 1970 Mustang Wiring Diagram Manual.

 

Next Question: do electrons go from + to - or from - to +?  Bonus points for knowing the true answer!

Randy,

The electrons still flow - to +.

From what I see in the '70 Cougar convenience group wiring diagram, The the Door Ajar circuit gets 12v from the yellow plug attached to the accessory terminal, which as you know has power when the key is in run and accessory positions. This 12v circuit supplies 12v to the low fuel warning light relay and to the door ajar warning light  The circuit is completed when the door ajar switch is grounded by the door being opened or partially opened. This is a separate switch from the common door jamb switch that turns on the interior lights and trips the key reminder buzzer.

That's how I looks to me in the diagram.

[RPM 1,157]

Damn, I sure hope there won't be a test later. I'm still working on colors this week, next week is numbers. 

[Caseyrhe 650]

I’m still wondering who’s on 1st

[Midlife 801]

10 hours ago, Rich Ackermann said:

Randy,

The electrons still flow - to +.

From what I see in the '70 Cougar convenience group wiring diagram, The the Door Ajar circuit gets 12v from the yellow plug attached to the accessory terminal, which as you know has power when the key is in run and accessory positions. This 12v circuit supplies 12v to the low fuel warning light relay and to the door ajar warning light  The circuit is completed when the door ajar switch is grounded by the door being opened or partially opened. This is a separate switch from the common door jamb switch that turns on the interior lights and trips the key reminder buzzer.

That's how I looks to me in the diagram.

Cougar and later Mustang door ajar (or key reminder) system is very different than the 70 Mustang.

Yes, electrons "flow from - to +" but in reality they don't.  It is the holes that actually move.

[69NC 21]

12 hours ago, Midlife said:

Ding Ding Ding!  We have a winner!

I knew that EE degree would pay off  :). How many bonus points do I get?

 

[Midlife 801]

69 bonus points!  Woohoo!