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Discussion Starter #1
I'm looking to set up my LED light bar to turn on with my high beams. I've spent the morning searching to no avail after a failed install last night. I used the following diagram to wire things up with the 85 terminal tapping into the stock high beam ground wire (white). Relay was a 40A being fed from the battery.



The issue was the LED light bar was on while the car was off and no lights on at all. After searching and searching I haven't found a clear description or set of instructions on how I can add a relay and trigger my light bar off the stock head lights. Can anyone here explain to me how I connect this relay correctly and tap into the high beams. I was using those Posi-Locks for tapping in.

 

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if im not to mistaken your rav's highbeams is controlled by the positive wire going to the headbeam.

so your trigger wire gotta be the positive one, and ground the other one ;)
 

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if im not to mistaken your rav's highbeams is controlled by the positive wire going to the headbeam.

so your trigger wire gotta be the positive one, and ground the other one ;)
That might make sense and make this a whole lot easier. I was under the assumption the lights were switched on the grounding. It seemed the information I had was that Positive (+) was always on the lights and the switch was ground (-)
 

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This is tricky because your high beams are also used by the DRL's. In other words there is voltage across the high beams when the headlights are off entirely, and when the high beams are on ( 6 volts in DRL mode, and 12V in High beam mode). Your relay will most likely operate at either of these voltages, (perhaps even hit and miss at 6v) so you need to come up with a more clever solution.

What is the maximum current and/or wattage rating of your LED bar?
 

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This is tricky because your high beams are also used by the DRL's. In other words there is voltage across the high beams when the headlights are off entirely, and when the high beams are on ( 6 volts in DRL mode, and 12V in High beam mode). Your relay will most likely operate at either of these voltages, (perhaps even hit and miss at 6v) so you need to come up with a more clever solution.

What is the maximum current and/or wattage rating of your LED bar?
It seems to work now when I did a simple relay fed off the high beam positive (+) line. Now it might get tricky like you said, as I am in a parking garage when doing this all so the normal DRL aren't on until its sunny and I'm outside..

These are the specs for the light bar...

Total Emitters: 42
Rated Voltage: DC 9-32V
Light Color: White
Power: 126W
Luminous Flux: 7560lm
Color Temperature: 6500K
Lifespan:: Up to 50000 hours
 

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So you are operating the relay (the coil) from the high beam positive to ground, and supplying the 12v source directly from the battery via a fuse?

If you connected to the + Left hand high beam, your LED bar will be on with the DRL's as well. If you connected to the + right hand beam, the above configuration may work for you.
 

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Discussion Starter #7
So you are operating the relay (the coil) from the high beam positive to ground, and supplying the 12v source directly from the battery via a fuse?

If you connected to the + Left hand high beam, your LED bar will be on with the DRL's as well. If you connected to the + right hand beam, the above configuration may work for you.
I am operating the light bar to switch with the high beams and fed with a 40A relay from the battery (fused)

When the DRLs come on so does the Light Bar it seems
 

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I used the following diagram to wire things up with the 85 terminal tapping into the stock high beam ground wire (white). Relay was a 40A being fed from the battery.

I think all you need to change in your original drawing is to connect pin #86 to ground, and connect pin #85 to the red wire on the Right Hand high beam.
 

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Discussion Starter #9
I think all you need to change in your original drawing is to connect pin #86 to ground, and connect pin #85 to the red wire on the Right Hand high beam.
I got all that and the system works now however, the DRLs at 6V are enough to trigger the relay and my light bar turns on with the DRL and the High Beams (as designed) I'm now thinking if I throw a few resistors into the circuit I might be able to reduce the current so it's only the high beams that truly activate the relay.

OEM DRL 6V -- minus 3V resistance (3V total) ---- Pin #30 relay
OEM High Beam 12V --- minus 3V resistance (9V total) -- Pin #30 relay
 

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OEM DRL 6V -- minus 3V resistance (3V total) ---- Pin #30 relay
OEM High Beam 12V --- minus 3V resistance (9V total) -- Pin #30 relay
I'm confused by this statement.

Are you saying that you have connected the +12 (red wire) of the high beam to pin #30 of the relay, and now plan on connecting a resistor in series with that wire?
 

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Discussion Starter #11
I'm confused by this statement.

Are you saying that you have connected the +12 (red wire) of the high beam to pin #30 of the relay, and now plan on connecting a resistor in series with that wire?
I may have wrote that out wrong.

I have Pin #86 working as my switch as its tapping the current from the DRL/High Beam positive (+) wire.

Pin # 30 is my battery to fuse to relay.

I'm wondering if I add resistors to my line from the DRL/High Beam to post #86 could I reduce the current enough to not trigger the relay while on DRL but have enough juice to switch when the high beams are activated.
 

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It should look something like this. It is important that you connect to the red wire on the RIGHT SIDE headlight and not the left side. You should not measure 6V at any point if it is wired this way.

Note that the connections to relay pins #85 & #86 can be reversed without affecting operation. The same is true for relay pins #30 & #87.

 

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It should look something like this. It is important that you connect to the red wire on the RIGHT SIDE headlight and not the left side. You should not measure 6V at any point if it is wired this way.

Note that the connections to relay pins #85 & #86 can be reversed without affecting operation. The same is true for relay pins #30 & #87.

Run pin 85 to the driver side High negative instead, and that relay should work. In DRL mode, there should be 0 measured volts. In HB mode, there should be 12.

Just be careful to take measurements; Toyota loves to play games with polarity.
 

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Run pin 85 to the driver side High negative instead, and that relay should work. In DRL mode, there should be 0 measured volts. In HB mode, there should be 12.
The two high beams are placed in series in DRL mode. The +12v is applied to the drivers side (LH) red wire, what you call the negative lead (white) is then connected to the white wire of the passenger lamp (RH) and the red wire of the RH lamp is then grounded.

+12v -----red----LH-Hi-Beam-----white------white----RH-Hi-Beam----Red---GND

So the voltage at the "driver side high negative" will be 6v relative to ground.
 
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