The low beams work, but when the highs are clicked on, nothing changes.
The bulbs are fine. Fuses are fine. Relay is fine.
Anyone know what’s wrong?
I’m guessing problematic multi-function switch. Ask shop for proper diagnois, probing circuitry vs schematic before replacing part. Do you hear a relay (possibly in engine compartment ) “click” when switching from low to hi- beams?
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No; standing next to the relay switch, I hear only the sound coming from inside the vehicle made by the lever on the steering column.
That’s consistent with faulty MF switch. Other possibilities though.
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Thank you. How do I test it? Would a multimeter work?
Do you have that section of the electrical diagram? If so, you are welcome to post it here for more ideas. Very hard to test without the diagram. Aftermarket repair manuals like Haynes, Chiltons usually include that diagram.
I’ll check for it after work.
Never trust the electrical diagrams in a Haynes or a Chiltons manual.
Learned that lesson a looooooong time ago.
Tester
For fun I was watching the guy rewiring his Morris. They use about 20 different colored wires and he said the same thing about the after market manual. Green with a red chaser versus red with a green chaser can provide surprise results. Another reason I’m glad I sold mine in 1966.
I found the Haynes manuals lacking in many areas. They tell you to remove something. There are pictures that show the part in the car, but don’t offer removal instructions. Sometimes it’s easy, sometimes it isn’t but it’s up to the DIYer to figure it out on his own. At least on all the repairs I wanted to make. Lots of instructions for removing an engine, but I never wanted to do that.
Yeah I have a couple Haynes or whatever, and the have detailed engine overhaul instructions. I never could understand why. I have to believe that 90% of us would never do that. But they never tell how to get the dang door panel off. Factory manuals are great for the detail but now you have to buy the body manual and electrical one. So comparing $400 to $30 guess just a trade off.
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Why do folks use high beams in town? I use my driving lights. got this to try and fix my headlight issue.
I own both the Haynes and the factory service manual for my Corolla. Hayne’s electrical diagrams aren’t as comprehensive, missing some info, some info incorrect; but if I only had the Haynes diagrams, that would be far better than having no wiring diagrams at all. Like our esteemed colleague @Bing says above, it’s a compromise.
Ah!
Now I know where George’s mindset is at.
Misinformation is better than no information at all/
That explains it!
Tester
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lol … that’s one way to look at it I guess. If I was lost in the woods I’d rather have a wet match than no match at all.
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Just sayin my factory body manual for a previous car had illustrations or actually pictures of the wire harnesses, how they were routed, and the PIN numbers. Pretty good detail compared to a Haynes that would only show a schematic and maybe not five pages of schematics showing every circuit. So if you need the information every day to earn a living it is worth it. Otherwise it a cost.benefit equation. Then of course there is YouTube and car talk which may or may not provide the missing pieces. Then of course there is the age factor limiting how much a person wants to crawl around fixing something.
I live in the suburbs and always use my high beams unless I am approaching oncoming traffic or following closely behind another car. It’s the only way I can see deer on roadside before it’s too late.
Before digging into anything wiring- are you sure your “headlights” are actually on, and that you aren’t just driving with your “Daytime Running Lights” on?
Daytime running lights use the headlights, but often at a lower voltage, and will not work the high beams. In our Toyota, it can be a challenge to know if we are on DRL versus actual headlights from inside the vehicle.
I see lots of vehicles running on just the DRL’s at night, and folks have no idea that their tail lights and clearance lamps aren’t even on. Verify this before tearing anything apart.
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Depends on the manufacturer.
Implementations
Depending on prevailing regulations and equipment, vehicles may implement the daytime-running light function by functionally turning on specific lamps, by operating low-beam headlamps or fog lamps at full or reduced intensity, by operating high-beam headlamps at reduced intensity, or by steady-burning operation of the front turn signals. Compared to any mode of headlamp operation to produce the daytime running light, functionally dedicated DRLs maximize the potential benefits in safety performance, glare, motorcycle masking, and other potential drawbacks.
Tester
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