JKmotorsports
tahoeyukonforum.com
Well, we all know that our trucks turn off the low beams when we switch to highs. Here is a way to have your lows and highs on at the same time.
00-02 model trucks will need a standard 12V automotive type relay. You can find a relay at just about any auto parts store.
03-06 models only need a diode. You can get this at Radio Shack or similar. Also, if you have a digital multimeter, this will be handy for circuit verification.
You will also need a way to splice your wire connections (solder, t-taps, etc. I ALWAYS use solder and heatshrink over connectors due to the greater reliability and less electrical property losses of soldered connections).
Pre-03 models
Behind the driver's side headlamp assembly, locate the harnesses to the low and high beam bulbs. The low beam should have a yellow and an orange wire. The high beam should have a purple and an orange wire.
The relay contacts are going to be wired as followed, and you only need to perform this on one side of the vehicle:
Relay Pin #
85 - Connects to purple wire from high beams.
86 - Connects to either orange wire, doesn't matter which.
30 - Ground.
87 - Connects to yellow wire from low beam.
87a- Not used.
Now turn on your headlights, switch to high beams and make sure all four lights are on at the same time.
03-up models
You will need to locate the BCM, which is underneath the driver's side dash.
Locate connector C2, which will be gray.
Locate pin B1, which is a black wire with a white stripe. Verify with a digital multimeter that this wire sees ground when you turn the high beams on. Connect the cathode end of the diode (the end with the band around the diode) to this wire.
Next locate pin A4, which is a pink wire with a white stripe. Verify that this wire has ground when the low beams turn on. Connect the other end of the diode to this wire.
That's it. Now turn on your headlights and switch on your high beams and make sure all four are on.
00-02 model trucks will need a standard 12V automotive type relay. You can find a relay at just about any auto parts store.
03-06 models only need a diode. You can get this at Radio Shack or similar. Also, if you have a digital multimeter, this will be handy for circuit verification.
You will also need a way to splice your wire connections (solder, t-taps, etc. I ALWAYS use solder and heatshrink over connectors due to the greater reliability and less electrical property losses of soldered connections).
Pre-03 models
Behind the driver's side headlamp assembly, locate the harnesses to the low and high beam bulbs. The low beam should have a yellow and an orange wire. The high beam should have a purple and an orange wire.
The relay contacts are going to be wired as followed, and you only need to perform this on one side of the vehicle:
Relay Pin #
85 - Connects to purple wire from high beams.
86 - Connects to either orange wire, doesn't matter which.
30 - Ground.
87 - Connects to yellow wire from low beam.
87a- Not used.
Now turn on your headlights, switch to high beams and make sure all four lights are on at the same time.
03-up models
You will need to locate the BCM, which is underneath the driver's side dash.
Locate connector C2, which will be gray.
Locate pin B1, which is a black wire with a white stripe. Verify with a digital multimeter that this wire sees ground when you turn the high beams on. Connect the cathode end of the diode (the end with the band around the diode) to this wire.
Next locate pin A4, which is a pink wire with a white stripe. Verify that this wire has ground when the low beams turn on. Connect the other end of the diode to this wire.
That's it. Now turn on your headlights and switch on your high beams and make sure all four are on.