FOOTWELL LIGHTS dimming with map lights and turning back on with headlights

Thread Starter

paki

Joined Dec 16, 2022
28
Can I use same ground for pins 85 on both relays and pin 87 of RL2 or do i need to use diffrent grounds for each relay
 

MisterBill2

Joined Jan 23, 2018
18,176
I still do not understand the motivation to have the foot-well lights on while the doors are closed. What purpose is served by having them on when the door is closed and so nobody is stepping into the foot-well?? And certainly, for most car brands, the door ajar switches close to the body ground when the door is opened. Thus normally the illumination negative side is switched.
And the way to avoid needing a second relay because of the DRL function will be to use the tail-lights feed rather than the headlight feed. Then no additional relay would be required, thus avoiding the need to interrupt the DRL feed circuit.
 

Thread Starter

paki

Joined Dec 16, 2022
28
I like it to glow at night like some sort of ambient lighting. Is it realy that bad to connect 2 relay on headlight source
 

MisterBill2

Joined Jan 23, 2018
18,176
My reason for suggesting to use the tail light feed iis ONLY because the headlight feed also gets the DRL voltage and that would probably operate the relay when the headlights were off.. I described that in my most recent post. The tail lights come on along with the head lights so that will satisfy your requirements, BUT the tail light circuit is OFF when the headlights are off. So no extra logic is required.
 

Thread Starter

paki

Joined Dec 16, 2022
28
Hi, guys im interested if this circuit is correct. The purpose of circuit on the left with relay 1 would be that when I unlock the car drl turn on and then after 10s turn off and they would do the same thing when i lock the car something like guide me home. Drl are switchback so they would flash yellow when i unlock and then would turn to white drl light. Relay 2 is from other circuit in post above in short the drl turn off when its dark outside.
Resistors: 1K, 10K, 100K
Electrolytic capacitor: 330uF/25V
Transistor: 1x BC557B (ex eq)
Diodes: 1N4007 and 2x IN5408(connected to drl)
Relay 1: 12V /10A

circuit (1).png
 
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sghioto

Joined Dec 31, 2017
5,380
I suggest making the changes shown below.
Q1 to a BC327 to handle the current and rewire switching the high side which is more efficient.
When the constant 12V is first applied relay 1 will activate for several seconds.
Relay 1 will activate while the Map lights are ON and stay on for an additional 10 seconds appx when OFF.
View attachment 287559
1676399537697.png
 
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MisterBill2

Joined Jan 23, 2018
18,176
Certainly D4 across RT2 is not needed because the headlights across the coil dap any spike that might try to develop, D2 is not required because the transistor is slowed by that ten second RC time delay constant,
The circuit as presented works fine, I did not check to verify the transistor was a good choice, but it probably is.
 

Thread Starter

paki

Joined Dec 16, 2022
28
Guys, in circuit on post #39 i used car relays 12V 40/30A im thinking of changing them to 12V 10A and put everything on perfboard. Would that be fine?
 
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