R60/5 headlight and tail light stopped working, bike turns on fine

Discussion in 'Airheads' started by DylanGolden, Apr 5, 2021.

  1. DylanGolden

    DylanGolden Adventurer

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    Hi folks, haven't posted on here in a long time but I noticed my lights stopped working but the battery seems fine and the gauge lights seem fine. Anyone have any suggestions for what it might be? I did get a new key a few months ago but they were working for the last three months. Of course I only rode it about ten times because it was freezing in Oklahoma.
    #1
  2. Pokie

    Pokie Just plain Pokie.

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    What year is the /5? Does it have fuses in the headlight (1972 and 1973)? If so, I'd start by checking the fuses, then the bulbs.
    #2
    Jim Day and groop like this.
  3. Beemerguru

    Beemerguru Beemerguru...G/S guy

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    Taillight is fused..headlight isn't. Against all odds, check the simple things first..like the light bulbs. Headlight..both high and low beam out? Does the brake light work?

    Also check the grounds at the battery and under the tank
    #3
  4. DylanGolden

    DylanGolden Adventurer

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    It's a 71. I haven't really checked anything yet but now that I know there are fuses to check I will start there.
    #4
  5. TwoShoes

    TwoShoes Carbon-based bipedal life form

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    The '71 likely won't have fuses to check
    #5
  6. DylanGolden

    DylanGolden Adventurer

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    Yeah both low and high beam don't work but the tail light and brake light work. You think it's just a headlight out? If so are those hard to come by or is it an item I can get at an auto parts store?
    #6
  7. Plaka

    Plaka Brevis illi vita est

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    Low and high beam are on different circuits. Blowing both filaments would be a rare situation. You have a wiring problem.
    #7
  8. Warin

    Warin Retired

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    Some people blow low beam and travel on hi beam for some time. Hi beam blows and they forget that low beam went out some time ago and think the have a fault.. (they do, called forgetfulness).

    Issues that can cause both beams to go out (ignoring the above forgetfulness);

    Earth connection from bulb to ground (includes bulb socket, brown wire and bolting to frame)
    Power connection from hi/low beam switch towards battery (includes switch contact, wire, connector, the next wire, etc).
    #8
  9. Pokie

    Pokie Just plain Pokie.

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    A noob question here,... when you press down your key and turn the key either left or right, do you get the park light to come on? One direction is the park light, the other direction is the headlight.

    If you have an H4 conversion, you can get those from any auto store. If it has the stock headlight, you might be able to fid it at a sportscar specialty store but likely not at a regular auto store. The fact that both beams are out, you either have a grounding problem or power problem. You are going to have to pop off the headlight and do some testing. I'd start with testing the bulb, then the power from the switch. Be careful with the wiring at the headlight bulb and park light bulbs, it's common for folks to hook the wires up backwards and short out the light. Just remember, brown is ground, yellow is low beam, white is high beam, gray is the park light, red is raw power and green is switched power.
    #9
  10. DylanGolden

    DylanGolden Adventurer

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    cool I’m gonna check the ground. Neither high or low beam work and I think both stopped working at the same time but I’m not positive.
    #10
  11. tlub

    tlub Long timer Supporter

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    While you are at it, get a wiring diagram, and practice following circuits with a multimeter. Do the ones that work as well. It will help the learning process.
    It could also be a bad handlebar switch. Or what others said. But really, being able to follow circuits is a basic, needed skill if you own one of these. It's not difficult.
    BTW, there are many other needed skills. Remember that these bikes were built when cars needed points and plugs at 5000 mile intervals, and valve adjustments, a grease job (bet you don't even know what that is :yum), and carburetor adjustments, and gas stations were actually service stations, because all vehicles needed so much more attention than now. Oh, and getting rings and valves done at 60,000 miles was a 'good car'. Many car manufacturers only just had been begun including oil filters in the past 10 years.
    You will get to know your vehicle better because of it.
    BTW, a stock /5 headlight bulb is available from any of the usual BMW parts suppliers. Bobs, Bench Mark Works, and many others. They have a different base than many other bulbs. You will not find them at NAPA or AutoZone.
    Here is one on ebay:
    https://www.ebay.com/itm/2729466787...3kvZhZ0xLBWRGOrmurKOUNuLXzvlFQcBoCgNMQAvD_BwE
    But I would recommend getting an H4 conversion kit if you don't already have one. They are much brighter, and bulbs are available everywhere.
    #11
  12. DylanGolden

    DylanGolden Adventurer

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    You are correct I don’t know what a grease job is but sounds sexy. I’ve replaced some electrical parts on it before but that was on a R100/7. I just had the clutch replaced before my mechanic quit and joined the military. Now there are no mechanics in tulsa willing or able to work on it. I have a multimeter and a manual. What is the setting my multi meter should be on to test things? Sorry these are dumb questions but I want to keep this thing on the road as long as possible. I also don’t have a ton of time to learn this stuff but I would love to know how to work on them. I also have a 63 Honda CA95 that’s got some metal banging around in the engine and won’t move forward anymore and a 65 Honda S65 that has a broken second gear fork (again) it’s the second time it’s broken in two years so I want get rid of that one, it seems to be a common issue.

    on the BMW I checked the ground cable and battery cables are all on there tight and secure so I’m guessing the bulb may be out.
    #12
  13. dave0

    dave0 Been here awhile

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    Set the meter on DC volts. you only need to see up to 15V.

    Read the multimeter manual WHILE you figure it out. Less chance of screwing up, and to re-enforce the learning.
    #13
  14. Warin

    Warin Retired

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    To check you have the multimeter correct ... measure the battery voltage accross the battery ... red lead to battery positive terminal, black lead to battery negative terminal .. should get ~ 12 volts ..

    Once that is ok .. measure the voltages on the headlight globe .. 3 connections to measure .. the black lead should remain on 'ground' - any bit of bare metal (not paint).

    Should get ~ 12 volts on one connection and ~0 volts on the other 2 connections. If you have that then the globe should light.

    Note the ~12 volts ... means around 12 .. could be 11 .. could be 13 ... somewhere around 12. Similar for ~0 .. 0.9 would be meh ok bit high.

    Oh if you have a 6 volt system .. just change the 12 for 6. 11 becomes 5 and 13 becomes 7.
    #14
  15. tlub

    tlub Long timer Supporter

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    A grease job wasn't sexy, but like many sexy things, was messy. It was greasing all the suspension and steering pivots with a pressurized apparatus called a grease gun, injecting grease through special fittings called Zerk fittings, or sometimes a needle fitting. You have several of these on your bike. And they need to be greased. You need to do this.
    You can also check for continuity using the ohms setting on the multimeter, when the bike is not turned on. The 15V setting tells you if something is getting 12v when turned on. The ohms setting tells you if the circuit is good. It is also how you check things like the coils or alternator rotor.
    An ohmmeter is another way of checking if a bulb is burned out. A burned out filament has no continuity, or put another way, infinite resistance.
    If you are thinking of treating this bike as something you take to the mechanic, I would recommend you change that thinking. These were made in the day when most people did their own maintenance. They were designed to be owner-maintained. The owner's manual is written with that in mind. Only the relatively wealthy, then and now, did not do their own maintenance.
    There are several good set of YouTube videos out there, and much advice on these pages. Paradoxically, you have more resources to learn this than we did when these bikes were new. But we also grew up experiencing hands on maintenance of everything, so it came more naturally.
    #15
  16. groop

    groop So much to ponder

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    So, related story from a not-so noob, but clearly a noob mistake. I had no brake light on my 77S last weekend. I pulled the bulb. Both filaments were intact. Running light worked fine. I started checking grounds, switches for continuity at the connectors. Finally pulled the tank and headlight bucket looking for wire breaks, blown fuses and wiggly relays. All looked great.
    So then I went back to the brake light and used my multimeter to check for continuity on the brake circuit when I applied the brake pedal. Had juice. Swapped a new bulb. Everything works fine now. An hour I will never get back, but chalk that one up to a learning experience.
    #16
  17. Pokie

    Pokie Just plain Pokie.

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    Another thing you have to watch for is the brake switch wiring getting pinched between the frame and the flange on the swing arm, where the boot clamp is. The easy fix here is to just strap down the wire so it doesn't cross the frame in the area of the boot clamp.
    #17