Wiring LED fogs to stock fog light switch

Elvira's Dad

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Hello!
First post! I'm a new owner of a 99 TJ, and I'm installing LED fog lights on it. The wire from the interior switch that goes to the original fogs is C203 according to the wiring diagram. I want to use it so it's interlocked with the headlight switch as original. I'm having trouble taking down the exact location of this wire in the engine compartment. Has anyone used this wire and can point me to it?
Thanks!
 
Hello!
First post! I'm a new owner of a 99 TJ, and I'm installing LED fog lights on it. The wire from the interior switch that goes to the original fogs is C203 according to the wiring diagram. I want to use it so it's interlocked with the headlight switch as original. I'm having trouble taking down the exact location of this wire in the engine compartment. Has anyone used this wire and can point me to it?
Thanks!

look and see if the old fog light plugs are coming out the front, you could just use those
 
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Hello!
First post! I'm a new owner of a 99 TJ, and I'm installing LED fog lights on it. The wire from the interior switch that goes to the original fogs is C203 according to the wiring diagram. I want to use it so it's interlocked with the headlight switch as original. I'm having trouble taking down the exact location of this wire in the engine compartment. Has anyone used this wire and can point me to it?
Thanks!

Welcome

As mentioned, look for the original plugs up under the front fenders.
 
They're there, but the plugs are different and the new lights have 30A fuse. I just want to use the stock wire to go to the fog light relay.
 
They're there, but the plugs are different and the new lights have 30A fuse. I just want to use the stock wire to go to the fog light relay.

The fuse in the PDC feeding the factory fog lights is 20A and the wiring feeding the factory fog lights are 18 ga; which means the factory fog lights draw about 7 amps each.
Since a 30 amp fuse is included with your LED foglight wiring harness; what is the wattage rating of each LED foglight ?
IF each of those LED fog lights is rated to draw more than 8 amps; I would not wire them directly into the factory fog light circuit without using a relay.
You risk the chance or overheating the circuit due IF the LED lights are rated to draw a higher amperage.
You can use the factory fog light wiring to engage the LED fog light relay by cutting off the connector; attaching the light blue to the positive relays (coil) wire and the black to the ground relays (coil) wire. You will need to connect the 30A power wire to the battery and the ground power lead to a chassis ground.
 
The fuse in the PDC feeding the factory fog lights is 20A and the wiring feeding the factory fog lights are 18 ga; which means the factory fog lights draw about 7 amps each.
Since a 30 amp fuse is included with your LED foglight wiring harness; what is the wattage rating of each LED foglight ?
IF each of those LED fog lights is rated to draw more than 8 amps; I would not wire them directly into the factory fog light circuit without using a relay.
You risk the chance or overheating the circuit due IF the LED lights are rated to draw a higher amperage.
You can use the factory fog light wiring to engage the LED fog light relay by cutting off the connector; attaching the light blue to the positive relays (coil) wire and the black to the ground relays (coil) wire. You will need to connect the 30A power wire to the battery and the ground power lead to a chassis ground.

I agree. That's why I specified I wanted to use the stock switch wire for the relay. Everybody's telling me to chop up the stock harness, which I clearly don't want to do.
Again, does anyone know where the C203 wire is routed in the engine compartment?
I know there are easier ways, but I want to maintain the stock integrity of the Jeep as much as possible.
I didn't think it would be this hard to get an answer.
Thanks!
 
I agree. That's why I specified I wanted to use the stock switch wire for the relay. Everybody's telling me to chop up the stock harness, which I clearly don't want to do.
Again, does anyone know where the C203 wire is routed in the engine compartment?
I know there are easier ways, but I want to maintain the stock integrity of the Jeep as much as possible.
I didn't think it would be this hard to get an answer.
Thanks!

If you don’t want to chop up the stock harness, then what do you plan to do when you locate the wire you are looking for?

All you need to do is connect your new fogs to the existing fog connector… you are going to need to chop something…
 
30amp seems way too much if these LED lights are drawing that much current they should not be used as fog lights.
Most LED flood light pods are way under 50w each so that is under 10amps of load

If you can verify what the wattage is of each light and then verify they draw less than 20 amps as other have stated just cut the stock connector and use something like this and be done.
https://www.amazon.com/Connector-wa...-Connection/dp/B08579V5ZJ/?tag=wranglerorg-20

Here is a watt to Amps calculator.:
https://www.rapidtables.com/calc/electric/Watt_to_Amp_Calculator.html

I think you may be getting confused we are only referring to the very end connector at the front of the jeep not the stock wiring harness under the dash or by the switch.
 
Again, does anyone know where the C203 wire is routed in the engine compartment?

I believe the C203 harness connector is one of the connectors that is attached to the center of the firewall above the valve cover.
You will need to trace out the wiring to ensure which one of the two it is....