100W aux lights, simple noob wiring question.
- Thread starter Randy88FJ62
- Start date
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- Thread starter
- #22
I will try the first diagram after work today. I have an extra inline fuse I can use. Why is the extra fuse required in the first diagram?
Thank you for taking the time to make the diagrams.
Thank you for taking the time to make the diagrams.
- Thread starter
- #23
While I’m waiting to go home and try out the wiring I’m also curious about the load on the alternator. How much load can be put on the stock electrical system without having to add a second battery or upgrading the output of the stock alternator?
ToyotaDon
I am here
Randy, is the switch lighted? That would be the only reason to have it connected to ground with the way you are set up. Before anything else, try disconnecting the ground wire since that would blow your fuse if the switch is wired wrong.
To check the switch, connect only the 12V wire, then switch it on, and check the other wires with a test light. I say to use a test light since a meter would still see 12V through the bulb of a lighted switch. Whichever terminal will power the test light is the one you want to connect to the relay. Then try grounding the other terminal and make sure the switch lights up. You may even get it to light while checking with the test light.
HTH
To check the switch, connect only the 12V wire, then switch it on, and check the other wires with a test light. I say to use a test light since a meter would still see 12V through the bulb of a lighted switch. Whichever terminal will power the test light is the one you want to connect to the relay. Then try grounding the other terminal and make sure the switch lights up. You may even get it to light while checking with the test light.
HTH
- Thread starter
- #25
Thank you Don, I will try that.
- Thread starter
- #26
When I hook up the lights directly to the battery with an inline fuse of 20 A it blows the fuse. I have ruled out the relay and the switch as sources of the blown fuses. If the two lights are 100 Watts each then their combined 200 Watt power, even with a low battery voltage of 11 V should only require a 18 Amps to run and should not blow a 20 Amp fuse...
Any ideas why the aux lights are playing games with me?
Please help.
Any ideas why the aux lights are playing games with me?
Please help.
.... Sounds to me like you have a direct short to ground . To find out if you have a short to ground.... Disconnect your ground connection for the lights, pull the fuse that keeps blowing ... Using an ohm meter measure how many ohms to ground from the load side of the fuse holder . In other words connect one lead to ground and the other to the load side of the fuse holder. There should be infinite ohms or OL on the meter . If you have any continuity to ground this may be why you are blowing fuses. Hope this helps
ToyotaDon
I am here
Yes, either there is a short in the circuit, or a short in one of the lights. You may want to try powering them individually with a fused piece of wire. Another trick is to use an automatic reset circuit breaker (ATO blade style) instead of burning up fuses.
- Thread starter
- #29
I only tested one of the lights before mounting them. I'll check the other one and try to find this short. While I am doing that, can anyone offer a good tech page or explain what a "switched ground" is?
NLXTACY
Wits' End
- Thread starter
- #33
First of all, NLXTACY. 
Second, thanks for the help.
Third: I installed a different pair of Toyota fog lights I got from Mot. They work great and wired in easily. They did not blow any fuses since they are 55W each. The 100W driving lights that I had previously tried to install did not ever work to my discontent. I can’t figure it out. Here’s the way I see it:
2, 100 W driving lights = 200 W of power needed. Let’s say I get spikes of low battery voltage of around 8 V. That means that the amerage required at max pull would be 25 A. I was using 12 Ga wiring with a total length of less than 20 feet. I tried using a 30 A fuse and blew it. My guess is that the length of the wire plus a theoretical low voltage spike could create higher amperage draw than expected? I was using a 40 A rated relay for this job so I believe that component of the system is ok.
What I’ve learned about car wiring over the last month:
-Relays are safe and effective switches lowering the length of thicker gage wiring.
-Inline fuses are placed as close to the battery as possible to minimize heated wire in case of a short, effectively preventing fires.
-Heat shrink, heat gun, electrical tape, and zip ties are my friend.
-Fuse blocks will be installed in the future to prevent massive amounts of inline fueses next to the battery.
So, back to the 2, 100 W lights. Your thoughts and solutions to my failure?
Second, thanks for the help.
Third: I installed a different pair of Toyota fog lights I got from Mot. They work great and wired in easily. They did not blow any fuses since they are 55W each. The 100W driving lights that I had previously tried to install did not ever work to my discontent. I can’t figure it out. Here’s the way I see it:
2, 100 W driving lights = 200 W of power needed. Let’s say I get spikes of low battery voltage of around 8 V. That means that the amerage required at max pull would be 25 A. I was using 12 Ga wiring with a total length of less than 20 feet. I tried using a 30 A fuse and blew it. My guess is that the length of the wire plus a theoretical low voltage spike could create higher amperage draw than expected? I was using a 40 A rated relay for this job so I believe that component of the system is ok.
What I’ve learned about car wiring over the last month:
-Relays are safe and effective switches lowering the length of thicker gage wiring.
-Inline fuses are placed as close to the battery as possible to minimize heated wire in case of a short, effectively preventing fires.
-Heat shrink, heat gun, electrical tape, and zip ties are my friend.
-Fuse blocks will be installed in the future to prevent massive amounts of inline fueses next to the battery.
So, back to the 2, 100 W lights. Your thoughts and solutions to my failure?
ntsqd
technerd
I would remove the connector wiring from the 100W lights (I'm assuming all was removed as a unit) and use an Ohm Meter check for a short to ground in each light individually and in the wiring.
Dump the electrical tape unless you're using the 3M self-fusing product. The regular tape is a short term solution on a vehicle. Heat & the various chemicals present break down the adhesive, leaving you with goo covered bare wires.
Dump the electrical tape unless you're using the 3M self-fusing product. The regular tape is a short term solution on a vehicle. Heat & the various chemicals present break down the adhesive, leaving you with goo covered bare wires.
- Thread starter
- #35
The 100 W lights are seperate and I need to make the wiring from scratch including the relay. Here's my method for wiring connections: Butt connector, cover with heat shrink, tape ends of heat shrink that don't close all the way, zip tie over electrical tape so it doesn't unwind in any way. It's overkill, but until i get a soldering gun and better connectors that's what i'm doing.
ntsqd
technerd
- Thread starter
- #37
You are now responsible for easily another $100 worth of wiring toys and goodies. I can't tell you how useful their catalog is. Thanks again.
Randy,
Very happy to hear that you've got the lights on and have them working w/o any drama!
Good luck with the other aux. lights!!
Thanks again!
