Headlight troubleshooting thread and how to aim your headlights.
I have had numerous requests for help in troubleshooting headlight problems. In order for a headlight UPGRADE harness to work properly, the stock headlights and the stock headlight harness must work correctly. So here is what I know about the headlights in these rigs. The FJ60 and FJ62 headlight circuits are nearly identical with a couple of exceptions. Here are the differences: the FJ62 has two extra high beam headlights, some of the wires are different colors, and the wiring positions in the headlight plugs are different. Please consult your Toyota Repair Manual (also called FSM) wiring diagram to troubleshoot your headlights.
The headlight switch is at the end of the turn signal lever. You twist it two clicks forward to turn on the head light relay. You should hear the relay click on. You can also turn on the headlight relay when the headlight switch is in the off position by pulling back the turn signal lever to "flash" your high beams. If you locate the relay, the wire coming from the wiring loom to the headlight relay is RED for both FJ60 and FJ62. This wire should always have battery voltage regardless of the position of the key. When the headlight relay is turned on, 12 volts is supplied through the RED/YELLOW wire to the two 15 amp headlight fuses for an FJ62, and through another RED wire to the two 10 amp headlight fuses for an FJ60. The headlight(s) on either side of both rigs are fused independently. If the relay clicks on, and both fuses are good, then you should have 12 volts out to each headlight via a RED/WHITE on the left and a RED/BLUE wire on the right for FJ62s, and a RED/WHITE wire on the left and a RED/BLACK wire on the right if you have an FJ60. For both rigs, the RED/YELLOW wire coming from the headlights is the HI beam ground wire and goes to the steering column HI/LO switch. The RED/GREEN wire coming from the headlights is the LO beam ground wire and goes to both the steering column HI/LO switch and the Hi Beam Indicator in the dash.
So, the first step in troubleshooting your headlights is to turn your headlight switch on and with either a voltmeter or a test light, verify that you have 12 volts out at each headlight. Make sure you use a good vehicle ground point for your test probe. If you don't have 12 volts at each headlight (yes all four for an FJ62 and both for an FJ60), then you have a bad relay, bad fuse(s) or a broken or cut wire. You will need to find and fix the problem before you can continue troubleshooting.
Toyota uses what we call "switched ground" to select Hi or Lo beams. So, to recap, all the headlights get 12 volts when you turn on the headlight switch. You select either Hi or Lo beams by completing the path to ground through the turn signal lever forward/back position. When the turn signal lever is pushed forward, the ground path is established for the Hi beam headlights. When the turn signal lever is pulled back, the Lo beam headlights have a path to ground. Pulling the turn signal lever all the way back is the spring loaded "flash" position and will light the Hi beams. Release the turn signal lever, and it should return to the Lo beams position.
So, if you have 12 volts at all the headlights, but either Hi beams or Lo beams are not working, you most likely have a bad Hi/Lo switch that is not completing the path to ground properly for either the HI beams, the LO beams, or both (see exception below before you tear into your steering column). Here is a good thread for disassembling the Hi/Lo switch in the steering column. If cleaning the switch does not restore the ground connections, then you may need to replace the switch.
https://forum.ih8mud.com/60-series-wagons/110746-high-beam-lights-fixed-finally.html
and this one:
https://forum.ih8mud.com/60-series-wagons/345255-high-beam-fix-writeup.html
There is one exception. If neither Lo beam headlight works, AND your high beam indicator light in the dash does not work when you turn on your Hi beam headlights, then the culprit is most likely both low beam headlights are burned out. This can happen if you frequently drive with your Lo beam headlights on during the day for visibility. Both may burn out without you realizing it.
If the high beam indicator in the dash comes on when your HI/LO switch is in the low position, AND your low beam headlights are not on, then you have a dirty or faulty combination switch.
The Hi beam indicator light in the dash works this way: It has a permanent path to ground. The other side of the indicator light is connected to the ground side of the Lo beam headlights. When the Lo beam headlights are on, the ground side of the Lo beam headlights is grounded through the HI/LO switch, and both sides of the Hi beam indicator light are at ground potential. When you switch to Hi beams, the ground to the LO beam headlights is removed, and the HI Beam Indicator has a path to 12 volts through the LO Beam headlight filaments which act as a wire for the very low wattage indicator light, and the non grounded side of the Hi beam indicator light "floats" up to 12 volts through the LO beam headlight elements.
So that's it. You now know how the headlights work, what color the wires are and what to expect on each wire. Use your volt meter or your test light to track down where your problem lies. Once your stock wiring is working, you are ready to upgrade your headlight harness to relieve the stress on the stock wiring, the stock headlight relay, fuses, and the HI/LO switch in the steering column. A headlight upgrade harness will also allow you to use higher wattage headlights that really light up the night.
EDIT: See post #6 in this thread for how to aim your headlights.
I have had numerous requests for help in troubleshooting headlight problems. In order for a headlight UPGRADE harness to work properly, the stock headlights and the stock headlight harness must work correctly. So here is what I know about the headlights in these rigs. The FJ60 and FJ62 headlight circuits are nearly identical with a couple of exceptions. Here are the differences: the FJ62 has two extra high beam headlights, some of the wires are different colors, and the wiring positions in the headlight plugs are different. Please consult your Toyota Repair Manual (also called FSM) wiring diagram to troubleshoot your headlights.
The headlight switch is at the end of the turn signal lever. You twist it two clicks forward to turn on the head light relay. You should hear the relay click on. You can also turn on the headlight relay when the headlight switch is in the off position by pulling back the turn signal lever to "flash" your high beams. If you locate the relay, the wire coming from the wiring loom to the headlight relay is RED for both FJ60 and FJ62. This wire should always have battery voltage regardless of the position of the key. When the headlight relay is turned on, 12 volts is supplied through the RED/YELLOW wire to the two 15 amp headlight fuses for an FJ62, and through another RED wire to the two 10 amp headlight fuses for an FJ60. The headlight(s) on either side of both rigs are fused independently. If the relay clicks on, and both fuses are good, then you should have 12 volts out to each headlight via a RED/WHITE on the left and a RED/BLUE wire on the right for FJ62s, and a RED/WHITE wire on the left and a RED/BLACK wire on the right if you have an FJ60. For both rigs, the RED/YELLOW wire coming from the headlights is the HI beam ground wire and goes to the steering column HI/LO switch. The RED/GREEN wire coming from the headlights is the LO beam ground wire and goes to both the steering column HI/LO switch and the Hi Beam Indicator in the dash.
So, the first step in troubleshooting your headlights is to turn your headlight switch on and with either a voltmeter or a test light, verify that you have 12 volts out at each headlight. Make sure you use a good vehicle ground point for your test probe. If you don't have 12 volts at each headlight (yes all four for an FJ62 and both for an FJ60), then you have a bad relay, bad fuse(s) or a broken or cut wire. You will need to find and fix the problem before you can continue troubleshooting.
Toyota uses what we call "switched ground" to select Hi or Lo beams. So, to recap, all the headlights get 12 volts when you turn on the headlight switch. You select either Hi or Lo beams by completing the path to ground through the turn signal lever forward/back position. When the turn signal lever is pushed forward, the ground path is established for the Hi beam headlights. When the turn signal lever is pulled back, the Lo beam headlights have a path to ground. Pulling the turn signal lever all the way back is the spring loaded "flash" position and will light the Hi beams. Release the turn signal lever, and it should return to the Lo beams position.
So, if you have 12 volts at all the headlights, but either Hi beams or Lo beams are not working, you most likely have a bad Hi/Lo switch that is not completing the path to ground properly for either the HI beams, the LO beams, or both (see exception below before you tear into your steering column). Here is a good thread for disassembling the Hi/Lo switch in the steering column. If cleaning the switch does not restore the ground connections, then you may need to replace the switch.
https://forum.ih8mud.com/60-series-wagons/110746-high-beam-lights-fixed-finally.html
and this one:
https://forum.ih8mud.com/60-series-wagons/345255-high-beam-fix-writeup.html
There is one exception. If neither Lo beam headlight works, AND your high beam indicator light in the dash does not work when you turn on your Hi beam headlights, then the culprit is most likely both low beam headlights are burned out. This can happen if you frequently drive with your Lo beam headlights on during the day for visibility. Both may burn out without you realizing it.
If the high beam indicator in the dash comes on when your HI/LO switch is in the low position, AND your low beam headlights are not on, then you have a dirty or faulty combination switch.
The Hi beam indicator light in the dash works this way: It has a permanent path to ground. The other side of the indicator light is connected to the ground side of the Lo beam headlights. When the Lo beam headlights are on, the ground side of the Lo beam headlights is grounded through the HI/LO switch, and both sides of the Hi beam indicator light are at ground potential. When you switch to Hi beams, the ground to the LO beam headlights is removed, and the HI Beam Indicator has a path to 12 volts through the LO Beam headlight filaments which act as a wire for the very low wattage indicator light, and the non grounded side of the Hi beam indicator light "floats" up to 12 volts through the LO beam headlight elements.
So that's it. You now know how the headlights work, what color the wires are and what to expect on each wire. Use your volt meter or your test light to track down where your problem lies. Once your stock wiring is working, you are ready to upgrade your headlight harness to relieve the stress on the stock wiring, the stock headlight relay, fuses, and the HI/LO switch in the steering column. A headlight upgrade harness will also allow you to use higher wattage headlights that really light up the night.
EDIT: See post #6 in this thread for how to aim your headlights.
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