With lots of people changing over to HIDs I thought this was worth a post. Since they require a heat up/cool down period, it's a great idea to disable the perimeter lighting feature on our trucks. I've seen this question asked a few times before. Mblouir wrote a how-to for the 04-present trucks, however, generation 10's with key fobs are much much different. Actually, the 97-03 model's do not have a programmable function to cut off the perimeter lights when locking the doors via keyless. I have had several members try to find something in their manual, but no such code exist for the general owner.
What is perimeter lighting?
When you press the unlock button with your keyless entry fob, the headlights come on for ~25 seconds or flash (depending on model). It is used to illuminate the exterior of the vehicle and give better visibility to the user while approaching the vehicle.
Why disable it?
The perimeter lighting feature will, to be blunt, greatly reduce the life of your HIDs. The constant flickering on and off from the perimeter lighting causes unnecessary wear on the bulbs since they don't have time to properly warm up or cool down before their next use. The ballast for the HIDs arent made for quick on and off periods, they require time to properly give off their rated wattage.
Electrical ballast - Wikipedia, the free encyclopedia
How to Instructions:
This mod is related to the flashing of lights that occurs when using the "LOCK" button on your key fobs. Also note, you can do the write up below, then use your dome light trigger to keep all of the following on until you hit the lock button on your remote. Thus unlock turns all lights on, Lock flashes all lights(minus heads) and then immediately turns them off.
So here is the remote/keyless entry module located under the steering column on the fire wall.
I couldn't find any schematics (no where online) for the box or the plugs, so i decided to take it apart to see what we were dealing with.
Looking at the picture above, I noticed: the three relays, (one that clicks when locking the doors). So i traced the input/outs to the 555timer/microchip. Their are 4 on the unit, but only one of them ran to the grey wire which can cut power to the perimeter lighting. Thus I traced that pin to the 555timer and sure enough, the 555/mircochip is controlled via a common threshold of 1/3 v of the output. This means all the light flashing via the keyfob is controlled by the grey wire. Moreover, you can't disconnect only the low beams or parking lights by this module. You can only disable both of them.
Once I figured that out, I had to trace the grey wire to a couple of relays, the ECM, and then finally to a box of relays under the passenger side dash panel.
Note: the box we are talking about is to the top right (on the passenger side dash, it is a big oval plastic over) it will have a plastic cover over the top that is about 2 feet long and 6-8 inches wide.
There is a small clip on the bottom of the box you need to pretty up to pull the box off the dash. Once you get it off the mounting bracket, there are two clips on both side you need to pull out to get the cover off.
Here is what is revealed.
I found 3 relays in the box and used my DMM to see which ones we need to look at. For simplicity, notice the way I am holding the box, it is in the same position as they were mounted. The top right and bottom right relays, are the only ones we are concerned with.
Now to simply disable *ONLY* the low beams when using keyfobs, pull the right bottom relay out of the box.
For those of you who dont want to enable fogs/aux's to flash, you are finished. All you had to do was pull that relay. Panic and everything still work, just the low beams wont flash using any of the keyless entry methods. This also disables DRL unless you cut pin 87a on the relay. Not a big deal considering the DRLs dont work half of the time.
What is perimeter lighting?
When you press the unlock button with your keyless entry fob, the headlights come on for ~25 seconds or flash (depending on model). It is used to illuminate the exterior of the vehicle and give better visibility to the user while approaching the vehicle.
Why disable it?
The perimeter lighting feature will, to be blunt, greatly reduce the life of your HIDs. The constant flickering on and off from the perimeter lighting causes unnecessary wear on the bulbs since they don't have time to properly warm up or cool down before their next use. The ballast for the HIDs arent made for quick on and off periods, they require time to properly give off their rated wattage.
Electrical ballast - Wikipedia, the free encyclopedia
How to Instructions:
This mod is related to the flashing of lights that occurs when using the "LOCK" button on your key fobs. Also note, you can do the write up below, then use your dome light trigger to keep all of the following on until you hit the lock button on your remote. Thus unlock turns all lights on, Lock flashes all lights(minus heads) and then immediately turns them off.
So here is the remote/keyless entry module located under the steering column on the fire wall.
I couldn't find any schematics (no where online) for the box or the plugs, so i decided to take it apart to see what we were dealing with.
Looking at the picture above, I noticed: the three relays, (one that clicks when locking the doors). So i traced the input/outs to the 555timer/microchip. Their are 4 on the unit, but only one of them ran to the grey wire which can cut power to the perimeter lighting. Thus I traced that pin to the 555timer and sure enough, the 555/mircochip is controlled via a common threshold of 1/3 v of the output. This means all the light flashing via the keyfob is controlled by the grey wire. Moreover, you can't disconnect only the low beams or parking lights by this module. You can only disable both of them.
Once I figured that out, I had to trace the grey wire to a couple of relays, the ECM, and then finally to a box of relays under the passenger side dash panel.
Note: the box we are talking about is to the top right (on the passenger side dash, it is a big oval plastic over) it will have a plastic cover over the top that is about 2 feet long and 6-8 inches wide.
There is a small clip on the bottom of the box you need to pretty up to pull the box off the dash. Once you get it off the mounting bracket, there are two clips on both side you need to pull out to get the cover off.
Here is what is revealed.
I found 3 relays in the box and used my DMM to see which ones we need to look at. For simplicity, notice the way I am holding the box, it is in the same position as they were mounted. The top right and bottom right relays, are the only ones we are concerned with.
Now to simply disable *ONLY* the low beams when using keyfobs, pull the right bottom relay out of the box.
For those of you who dont want to enable fogs/aux's to flash, you are finished. All you had to do was pull that relay. Panic and everything still work, just the low beams wont flash using any of the keyless entry methods. This also disables DRL unless you cut pin 87a on the relay. Not a big deal considering the DRLs dont work half of the time.
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