How to Install a Factory Extended Idle Switch
02-28-2017, 09:13 AM
#17
maybe a diagram because the fog light switch has four wires from the pigtail harness and no other how tos were they using a relay it was just as simple as hooking up the wires and splicing. I just need to know if the issues is my fog light switch and needs to be replaced
03-14-2017, 05:45 AM
#19
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03-14-2017, 09:01 AM
#20
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Sorry, I'm completely new to this forum and more worried about screwing up the posts than I am being clear with things. To clarify, I do not have any of the fog light wiring, my Jeep never had it from the factory. where should I be wiring to since I dont have that harness to tap into? I hope that makes more sense.
03-14-2017, 10:14 AM
#21
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Year: 1996
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he made it so it looks factory, but you can use any switch you'd like to make it more simple. go to your local eletronic store, get an on-off switch and wire it so when you turn "on" the switch, it grounds pin A12, which will bump your idle.
and to correct OP it's not just 97-01, it includes 96 too since it was OBDII too
and to correct OP it's not just 97-01, it includes 96 too since it was OBDII too
03-14-2017, 12:59 PM
#22
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Sorry, I'm completely new to this forum and more worried about screwing up the posts than I am being clear with things. To clarify, I do not have any of the fog light wiring, my Jeep never had it from the factory. where should I be wiring to since I dont have that harness to tap into? I hope that makes more sense.
The actual circuit is very simple, as Cane said: Just have a switch that connects A12 to Ground. This can be done with your standard, boring toggle switch by simply connecting A12 to one side and Ground to the other. That's it.
If you do not own a factory EXT IDLE switch, that would be the simplest way to do it.
The factory switches is where it gets complicated because you have 12V+ thrown in there to power the two light bulbs in the switch--one for the backlight and one for the indicator light. Then you have to consider that the factory fog light switch is electrically different internally than the EXT IDLE switch, and you must use a relay.
I may just have to do a video this weekend.
Last edited by wizardpc; 01-31-2023 at 06:43 AM.
03-14-2017, 01:20 PM
#24
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Do you own a factory EXT IDLE switch?
The actual circuit is very simple, as Cane said: Just have a switch that connects A12 to Ground. This can be done with your standard, boring toggle switch by simply connecting A12 to one side and Ground to the other. That's it.
If you do not own a factory EXT IDLE switch, that would be the simplest way to do it.
The factory switches is where it gets complicated because you have 12V+ thrown in there to power the two light bulbs in the switch--one for the backlight and one for the indicator light. Then you have to consider that the factory fog light switch is electrically different internally than the EXT IDLE switch, and you must use a relay.
I may just have to do a video this weekend.
The actual circuit is very simple, as Cane said: Just have a switch that connects A12 to Ground. This can be done with your standard, boring toggle switch by simply connecting A12 to one side and Ground to the other. That's it.
If you do not own a factory EXT IDLE switch, that would be the simplest way to do it.
The factory switches is where it gets complicated because you have 12V+ thrown in there to power the two light bulbs in the switch--one for the backlight and one for the indicator light. Then you have to consider that the factory fog light switch is electrically different internally than the EXT IDLE switch, and you must use a relay.
I may just have to do a video this weekend.
03-14-2017, 01:55 PM
#25
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I'm doing a horrible job helping you understand my situation, but i've at least figured out this forum. I do have a factory EXT switch (snatched one of the ones on Ebay recently) and was mostly concerned with the backlight and indicator light wiring. What will I tie my orange wire and blue/white wire into since I dont have a fog harness to tap into?
To start, if you have a factory foglight pigtail tucked back there, you can just snip it off and use those wires. You will want to crimp the orange wire from the foglight harness to the orange wire from the EXT idle switch pigtail. Next, you will crimp the black wire from the foglight harness to the black wire from the EXT idle switch pigtail. You will not use the other two wires coming from the foglight pigtail, so just wrap them with electrical tape or twist on some wire ends.
Next, you need to wire in your ignition power source. Directly above the switch panel, you will see a wiring harness wrapped in black electrical tape. You can peel away some of this, and you will find 3 wires in the harness. One of the wires is blue with a white stripe, JUST LIKE the wire coming from your EXT idle switch. You need to splice the blue and white wire from your EXT idle switch pigtail into this wire because that's an ignition power source for your HVAC system.
The last wire, the gray one, gets spliced into your computer at pin A12. Pin A12 is the solid gray wire (again, same color as the switch) that is located inside of the first plug on the computer (facing the front of the vehicle). It is the first wire in the second row of the plug. Just snip this wire, run some of your 18 gauge wire (about 5-6 feet) through the firewall from the switch to pin number A12. The bottom piece of the wire that you snipped can be grounded to the chassis. There is a nice spot right under the computer.
Next, you need to wire in your ignition power source. Directly above the switch panel, you will see a wiring harness wrapped in black electrical tape. You can peel away some of this, and you will find 3 wires in the harness. One of the wires is blue with a white stripe, JUST LIKE the wire coming from your EXT idle switch. You need to splice the blue and white wire from your EXT idle switch pigtail into this wire because that's an ignition power source for your HVAC system.
The last wire, the gray one, gets spliced into your computer at pin A12. Pin A12 is the solid gray wire (again, same color as the switch) that is located inside of the first plug on the computer (facing the front of the vehicle). It is the first wire in the second row of the plug. Just snip this wire, run some of your 18 gauge wire (about 5-6 feet) through the firewall from the switch to pin number A12. The bottom piece of the wire that you snipped can be grounded to the chassis. There is a nice spot right under the computer.
03-14-2017, 02:48 PM
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03-14-2017, 03:00 PM
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04-19-2017, 11:21 AM
#28
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For those wondering, an Ebay seller has started selling AFTERMARKET EXT idle switches that are made to look like the factory switch.
Note the pigtail wiring is different, but it's a cheaper option to get this to work if you can't find or afford an OEM EXT Idle switch.
There are three wires instead of four: power, ground, and switched power. I would assume the one missing wire is the one that normally powers the built-in light bulb in the OEM switch, which is missing from the aftermarket one. So I think it would still wire up to pin A12 in your factory computer as indicated in this write-up.
http://www.ebay.com/itm/Rocker-switc...5YuNbP&vxp=mtr
Note the pigtail wiring is different, but it's a cheaper option to get this to work if you can't find or afford an OEM EXT Idle switch.
There are three wires instead of four: power, ground, and switched power. I would assume the one missing wire is the one that normally powers the built-in light bulb in the OEM switch, which is missing from the aftermarket one. So I think it would still wire up to pin A12 in your factory computer as indicated in this write-up.
http://www.ebay.com/itm/Rocker-switc...5YuNbP&vxp=mtr
04-20-2017, 01:58 AM
#29
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Year: 1999
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I wonder if that's a problem with the photo? The switch itself has four pins on it. The type of switch you just described wouldn't operate the extended idle function since it just needs to ground out the pin. 
04-20-2017, 07:40 AM
#30
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You'll need to connect that to a relay and use the relay to ground A12.