Printer Friendly Forum Posts - wire dome light to map light switch

2008 Mazda5.

The wife's one complaint with this microvan, is there isn't a way to turn on the rear dome light without reaching back and flipping the switch on the light just like in a car. This doesn't work while driving, and little ones can't reach it.

My solution was to wire the driver's map light switch to ground the door trigger too. This works, but who wants to drive with a map light in your eyes? Not Safe!

What I've determined I'd like to do now, is use maybe a momentary -> constant relay configuration to toggle the rear light on/off without leaving the map light on. But here's the way I'd like for it to operate if possible. The map light switch is currently switching ground.

1st push -> turn ON the map light

2nd push -> turn OFF the map light

3rd push -> turn ON the dome light w/o the map light (maybe with a time off delay)

4th push -> turn OFF the dome light

REPEAT. It would be great if a door opening would reset the switch too, but that may not be possible. Am I asking for too much?

It's a 3 wire system with...

Black - Ground (-)

Red - 12v constant (+)

Yellow - Door trigger switched ground (-)

Thank you for your help!

Aaron

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Aaron

After further consideration, it would be easier to just use the 'Latched On/Off Output Using a Single Momentary Pulse' relay setup with some modification. But I have some questions on that one. I will post in the 'Relays' forum for those.

Mods,

If this needs to be moved or deleted, please do so.

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Aaron

First off, does the 'Latched On/Off Output Using a Single Momentary Pulse' relay system work if the momentary push button is NOT momentary? Can the output be (-) ground instead of (+) positive? Also, can the 'Momentary to Constant' relay system be extended to about 10 minutes? Here's the way I need a circuit to work.

Push a button that provides ground to a map light (existing setup). to provide ground to the (-) door pin only on the second push.

1st push -> turns ON the map light (always has ground applied when pushed), this would activate the 10 minute off-delay and energize the Latched relay setup.

2nd push -> turns OFF the map light (removes ground)

3rd push -> turn ON map light again, but this time the ground causes the (-) door pin to be applied via the Latched relay setup.

4th push -> turn OFF the map light

5th push -> turn ON the map light and de-energize the Latched setup.

6th push -> Restart

This sounds like alot of steps, but the jist is that I don't want the door pin to be applied with the first (-) ground being applied via the map light switch, but the second.

Thanks

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Aaron

Sorry to keep adding to this, but I have another idea since finding this link within a post.

https://www....com/p-423-elk-960-delay-timer-module.aspx

Is there a way to send a pulse trigger with a quick on/off of the switch, but not if the switch is on for more than a couple seconds?

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Aaron

Can't its power be intercepted from the front?

Otherwise extend it or its trigger (door switch) to the front.

Else a relay that is turned on from the front (and rear as well if diodes are used) that connects either +12V or trigger path to the lamp.

The same power wire, ground and door trigger feed the map lights. That's how I'm able to have the map light switch ground the door trigger to turn it on now.

Running extra wires would require partially removing the headliner.

Adding an aftermarket switch would be simple, but unsightly. And it wouldn't allow a time off delay.

I have a schematic in mind and will post when I have it drawn for review.

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Aaron

So all this because someone leaves the rear light set to on? (I assume the usual 3-position switch - off, door, on?)

But I'll wait to see your schematic.

Here is the wiring diagram for a 2007 Mazda 5 courtesy light system.
It should be the same as the 2008 model year.
You can implement a DEI 528T pulse timer relay to do what you want.
It's similar to the timer you show above with a 1-90 second adjustable delay.
And it comes in an enclosure already.
Just another option.

Pity the upper-right ground G12 to the left D pillar cannot be extended and switched.

Thanks 91stt,

That definitely helps to clarify as the map light circuitry is not so obvious by looking at it when removed. But the DEI timer doesn't give me the 10+ minute duration I'm looking.

oldspark,

The ground is already there at the dome light and map light, and it's constant so that's not the issue. The issue is that I would like the ability control the 'Interior Light' without reaching back and flipping it's switch as it's not within reach of the driver. The solution is to use one of the map light switches to ground the YELLOW wire, but currently this keeps that map light ON which I don't want.

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Aaron

My bad!
I was thinking rear compartment light - not the dome light.

And I suppose it is unacceptable to keep the map light's door switch switch in the off position, and then merely ground any of the door switch outputs at the doors, or to or from the Body Control Module (behind the RHS of the dash)?

[FYI - That's a bit like my cabin lamp which has only door else on positions. It is normally in the door position, and the ground wire to the door switch(es) goes thru a 3-position rotary switch for off, door, or on. (It's actually a 4-position fan switch where the 4th position turned on under-dash flouros....) ]

That's how I have it now. The map light switch grounds the door pin, but since the map light switch has to be ON for this, the map light is always ON regardless of the DOOR/OFF switch position.

The goal of the circuit diagram I show is to quickly turn ON then OFF the EXISTING SWITCH, which would trigger the timer relay. But if the switch is ON for a second or two (like it would be if you wanted to use the map light), then the capacitor would charge and conduct which would activate the relay on the left, and cut power to the timer until the switch was turned OFF again. Then the capacitor would drain and everything would RESET.

Does this look like it will work the way I'm thinking? What capacitor/resistor combination would be required to give you a second or 2 before the capacitor charges? And how long would it take for the capacitor to drain and RESET?

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Aaron

Typo - ...activate the relay on the RIGHT, and cut power ...

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Aaron

Just seen the diagramme. Ground terminal 5a BROWN / red at the BCM, then do it through a latched rather than momentary switch, no timer required.
First rule for these projects:- KISS Keep it simple, stupid.

Once again, I'm NOT working on the 'Cargo Compartment Light' here on terminal 5A.

I'm working on the 'Interior Light' and 'Map Light' on terminal 6I.

Sometimes simple just won't do.

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Aaron

If you want to put the time into it and don't mind doing some assembly, you can build a timer circuit.
It is based on a 555 timer set up in monostable mode.
Here is a brief write up that may help.
It is not difficult to do and parts are readily available from places like digikey.com

https://www.eleinmec.com/article.asp?4

That's great. I've got a 555 timer. The problem is with all the components and a half-dozen relays to do a momentary latched on/off. I'm up to the price of a pre-assembled timer like the Altroix 6062 or ELK-960. I've got some pondering to do.

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Aaron

FLcruising wrote:

That's great. I've got a 555 timer. The problem is with all the components and a half-dozen relays to do a momentary latched on/off. I'm up to the price of a pre-assembled timer like the Altroix 6062 or ELK-960. I've got some pondering to do.

You do not need the extra relays for latching since the timer circuit will do that for you. You can go with a dual timer for added flexibility

Upon using several 555 calculators, it appears the longest duration I can get reliably with a 555 is about 4-5 minutes. Apparently it's not 'safe' to use anything greater than a 1mÙ / 100µF combination either. Any other ideas?

https://www.doctronics.co.uk/555.htm#monostable

https://www.kpsec.freeuk.com/projects/timer.htm

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Aaron

Well, this looks promising...

https://www.jaycar.com/productView.asp?ID=KD6014

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Aaron

91stt] wrote:

QUOTE=FLcruising]
That's great. I've got a 555 timer. The problem is with all the components and a half-dozen relays to do a momentary latched on/off. I'm up to the price of a pre-assembled timer like the Altroix 6062 or ELK-960. I've got some pondering to do.

You do not need the extra relays for latching since the timer circuit will do that for you. You can go with a dual timer for added flexibility[/QUOTE]

Yea, but I need to be able to turn the thing back off again without having to wait for the timer.

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Aaron

Not that I still understand why the dome light would be on unless its switch is left in the on position (or maybe it's off with ignition off?) instead of the door position.... etc etc

Just do the 555 calcs with the 10uF that Jaycar use. eg - 1MOhm for 10 secs.

And FYI - I often had problems using the dual timer (556?) and preferred use separate 555s. (That was was despite adequate PSU decoupling etc.)

FLcruising wrote:

91stt] wrote:

QUOTE=FLcruising]
That's great. I've got a 555 timer. The problem is with all the components and a half-dozen relays to do a momentary latched on/off. I'm up to the price of a pre-assembled timer like the Altroix 6062 or ELK-960. I've got some pondering to do.

You do not need the extra relays for latching since the timer circuit will do that for you. You can go with a dual timer for added flexibility

Yea, but I need to be able to turn the thing back off again without having to wait for the timer.

[/QUOTE]

If you modify the circuit in that article to pull pin 4 low momentarily so it will reset the output. This can be accomplished with a resistor and additional switch.