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I have a 2003 Toyota Camry, and the low beams do not work. However, the high beams do work. This is my diagnosis.

  1. I changed the low beam bulbs, and the low beams still don't work.
  2. I checked the 15A fuses for the low beams, and the fuses are not blown.
  3. I checked the relay by removing the relay from the fuse box and provided ~7V to the "small" terminals. I heard a click and checked continuity on the "large" terminals. The relay appears to be working fine.
  4. I checked the voltage at the bulb connectors when the low beams were on. There was no voltage drop. 0V on the multimeter.
  5. I checked if the bulbs were properly grounded. They were properly grounded. Therefore, they are not getting power.
  6. I checked the relay again by using the wand/stick that turns on the headlights. When I switch to low beams, I do not hear click. When I switch to high beams I hear a click.
  7. I checked the wiring diagram for a 2003 Toyota Camry. Head Light Circuit Diagram

  8. There is only one relay for both the high and low beams. Therefore, I think there should be a click for the low beams before the high beams. This does not happen.

My question is: is my relay the issue here? I would naturally assume the relay is the issue because it should click before the high beams are on. However, I got to thinking maybe it's the wand/stick that controls when the high or low beams are on because the relay works properly when the high beams are on. Plus, I checked the relay externally, and it appears to be working fine. Any guidance is much appreciated.

  • You probably did, but.... did you check that there was voltage at the 15A low beam fuse when the low beams were on? If there's voltage at the box and voltage into the relay, and when you put voltage to the relay you get voltage out of the relay, but no voltage to the low beams, then the wire is broken between the relay and the low beams. Just start at the earliest possible stage which you can access, and check every connection for voltage. – the_storyteller Mar 7 at 19:23
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    Yes I did. I believe I found the issue. It's the actual headlight control switch in the car. What I did was remove the bottom of the steering column to access the pins from the control switch. I unplugged it and found which pins were power, ground, and switches. I short the switches to power to see if the low beams turned on. They did turn on, so my guess is the headlight control switch or some call it the headlight stalk. Imma try to replace the part this weekend and update this post. Thanks for the tip though. – Alex M Mar 8 at 2:56
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Study the schematic. The switch matrix provides ground for selected circuits. The entry for Low Beam is the same as the entry for OFF: No Function. Furthermore the Low Beam bulbs have a hard wire ground as if Low Beam is always on while the car is in use.I would install NEW 15 amp fuses before leaving the Auto parts store if still have problem order a new relay.Furthermore trouble shooting with a 5-dollar Circuit Tester.is better than Volt meter-you'll see!

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