Factory Fogs With High-Beams (Tech Info)
12-22-2008, 05:32 PM
#1
JK Super Freak
Thread Starter
Factory Fogs With High-Beams (Tech Info)
Hi All,
OK, so everyone wants to run the factory fog lights with the high beams. The reasons are varied and do not matter. I also wanted to do this, so I enlisted a friend of mine that is a DCC Tech with access to all the DCC gizmos. Here is what we discovered using my '08 Rubi as a test subject:
Rubicons and Saharas that come with the fogs out of the factory (which is all of them): you can not reprogram the TIPM to allow the fogs to come on with the high beams. An X that has them added after the factory looks like they can be reprogrammed. The StarScan et al know if the Jeep came with fogs, and if it did, it sees no reason to allow you to access the software. We even tried changing the country code on the ECU to Canada and Rest Of World - no dice.
So, you are thinking, "Oh, OK, I'll just run a relay to switch on the fogs when the high beams are on.". BUT, that will cause a back feed into the TIPM and damage it, so do not do that.
After we sat there for a time, it looks like you'd have to use three (or four - depending on how you wire it) relays - one for each fog to isolate the TIPM power cable and one (or two) to provide power to the fogs. This means that when you turn on the high beams, the two relays disconnect (relays switch off) the TIPM wires, and allow the third (and fourth) to switch on and turn on the fogs.
Also, be very careful - the electronics in the JK are integrated into *everything*. Seriously, it even knew I was holding the high-beam flasher to keep the fogs on, and it knows I have removed the subwoofer. *All* electrical devices in the JK are monitored buy the system).
If you ever get the chance to use a StarScan (which, BTW, is a very slow machine) or the newer version (called WiScan, IIRC), do it, it really is interesting.
Hope that helps someone.
OK, so everyone wants to run the factory fog lights with the high beams. The reasons are varied and do not matter. I also wanted to do this, so I enlisted a friend of mine that is a DCC Tech with access to all the DCC gizmos. Here is what we discovered using my '08 Rubi as a test subject:
Rubicons and Saharas that come with the fogs out of the factory (which is all of them): you can not reprogram the TIPM to allow the fogs to come on with the high beams. An X that has them added after the factory looks like they can be reprogrammed. The StarScan et al know if the Jeep came with fogs, and if it did, it sees no reason to allow you to access the software. We even tried changing the country code on the ECU to Canada and Rest Of World - no dice.
So, you are thinking, "Oh, OK, I'll just run a relay to switch on the fogs when the high beams are on.". BUT, that will cause a back feed into the TIPM and damage it, so do not do that.
After we sat there for a time, it looks like you'd have to use three (or four - depending on how you wire it) relays - one for each fog to isolate the TIPM power cable and one (or two) to provide power to the fogs. This means that when you turn on the high beams, the two relays disconnect (relays switch off) the TIPM wires, and allow the third (and fourth) to switch on and turn on the fogs.
Also, be very careful - the electronics in the JK are integrated into *everything*. Seriously, it even knew I was holding the high-beam flasher to keep the fogs on, and it knows I have removed the subwoofer. *All* electrical devices in the JK are monitored buy the system).
If you ever get the chance to use a StarScan (which, BTW, is a very slow machine) or the newer version (called WiScan, IIRC), do it, it really is interesting.
Hope that helps someone.
12-22-2008, 06:51 PM
#2
Two system
I ran a separate wiring system complete with light plugs and relay and switch. This let me use a higher wattage bulb a 9005. Now i can use them on high or low
02-02-2009, 05:30 PM
#3
JK Newbie
Join Date: Jun 2008
Location: Lakeside, CA
Posts: 97
Likes: 0
Received 0 Likes
on
0 Posts
With two relays: Notice there are four diodes in the circuit to prevent back feeding the BCM
The four diodes are important to prevent any back feeding of circuits. Relay #1 becomes self sustaining until ground from relay #2 is lost. You would need to turn on the fog lamps during low beam operation but will stay on when switched to high beam.
The four diodes are important to prevent any back feeding of circuits. Relay #1 becomes self sustaining until ground from relay #2 is lost. You would need to turn on the fog lamps during low beam operation but will stay on when switched to high beam.
07-09-2009, 03:11 AM
#6
Eternal ***erator
Just DON'T use the factory wiring.
Unplug the fogs from the OEM circuitry, cap it off & pretend it no longer exists. (I did exactly that, but i used the factory foglight power as the trigger wire for a new relay, so my factory switch triggers my new foglight relay, which in turn powers up my fogs)
Install a relay/switch of your choosing and power them like any other set of aftermarket lights. Power off of the battery through the relay & hook up the trigger wire wherever it floats your boat.
Simple, relatively cheap, and with one relay you can make them sing & dance however you want them to, and the JK/TIPM wont know anything about it.
Unplug the fogs from the OEM circuitry, cap it off & pretend it no longer exists. (I did exactly that, but i used the factory foglight power as the trigger wire for a new relay, so my factory switch triggers my new foglight relay, which in turn powers up my fogs)
Install a relay/switch of your choosing and power them like any other set of aftermarket lights. Power off of the battery through the relay & hook up the trigger wire wherever it floats your boat.
Simple, relatively cheap, and with one relay you can make them sing & dance however you want them to, and the JK/TIPM wont know anything about it.
01-15-2012, 08:29 AM
#7
Just DON'T use the factory wiring.
Unplug the fogs from the OEM circuitry, cap it off & pretend it no longer exists. (I did exactly that, but i used the factory foglight power as the trigger wire for a new relay, so my factory switch triggers my new foglight relay, which in turn powers up my fogs)
Install a relay/switch of your choosing and power them like any other set of aftermarket lights. Power off of the battery through the relay & hook up the trigger wire wherever it floats your boat.
Simple, relatively cheap, and with one relay you can make them sing & dance however you want them to, and the JK/TIPM wont know anything about it.
Unplug the fogs from the OEM circuitry, cap it off & pretend it no longer exists. (I did exactly that, but i used the factory foglight power as the trigger wire for a new relay, so my factory switch triggers my new foglight relay, which in turn powers up my fogs)
Install a relay/switch of your choosing and power them like any other set of aftermarket lights. Power off of the battery through the relay & hook up the trigger wire wherever it floats your boat.
Simple, relatively cheap, and with one relay you can make them sing & dance however you want them to, and the JK/TIPM wont know anything about it.
Trending Topics
01-15-2012, 09:27 PM
#8
JK Freak
Join Date: Mar 2009
Location: Arvada, CO
Posts: 747
Likes: 0
Received 0 Likes
on
0 Posts
#1 - apparently it is illegal to run fogs with high beams. This explains the fact they go off from the factory, and the warnings from aftermarket foglight kits.
#2 - I can't see anything wrong with the wiring. Obviously it was done by someone with an understanding of electronics.
Just do it.
#2 - I can't see anything wrong with the wiring. Obviously it was done by someone with an understanding of electronics.
Just do it.
