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'90 K75S Rear Light Fault Warning Question

jkbales

New member
I recently bought a 1990 K75S, no ABS, that came without a manual. Can you help me figure out if my warning light is working right?

The rear light out warning light comes on solid when the ignition is turned on, and goes out when both front and rear brakes levers are first used. It stays out unless a bulb is bad (one was, so I know it works) but it never flashes. The brake switches and all lights work just fine, tail/brake lights go on and off exactly like they should.

I found a 1994 manual, which says that the rear light warning comes on solid with the ignition, and changes to flashing when you operate the brake levers, provided everything is working normally. It says it doesn't flash (I assume it stays on steady) if there's a fault. There is no mention of it ever going out, but it must at some point, otherwise it couldn't come back on if there's a fault while riding.

Does the flashing apply only if you have ABS? Is mine working right for a non-ABS bike?
 

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The flashing mode is for ABS bikes only. The flashing light should go out when the ABS bikes get above a couple miles per hour if everything is working correctly.


Your bike only has two modes: on or off. Some aftermarket taillight modulators will cause the light to flash when the brake is applied (Kisan).

The light test the brake light, both brake switches, AND the tail light.


:dance:dance:dance
 
Thanks. That's like the "brake failure" light on my RT, which flashes until you get moving. I know it's only doing it's ABS/ASC self check, but it unnerves some of my passengers. It's the last thing they want to see when boarding!
 
That threw me a bit when I went to an ABS K75 from an ABS2 K11.

On an ABS-I equipped bike - the bulb failure light behaves differently depending on what you do. Turning on the bike without having touched both brakes, the bulb light will be lit steady and ABS light blinking. Once you activate both front and rear brakes (doesn't have to be at the same time) the bulb light will then begin to flash along with the ABS light. Once you are underway the ABS and bulb lights will stop blinking. OK, if you do not touch both brakes, like I often do, the bulb light will stay steady lit even after you are underway and the ABS light has stopped blinking, until you do hit both of them.

As Lee said, without ABS the light should go out after you activate both brakes.
 
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Confused

That threw me a bit when I went to an ABS K75 from an ABS2 K11.

On an ABS-equipped bike - the bulb failure light behaves differently depending on what you do. Turning on the bike without having touched both brakes, the bulb light will be lit steady and ABS light blinking. Once you activate both front and rear brakes (doesn't have to be at the same time) the bulb light will then begin to flash along with the ABS light. Once you are underway the ABS and bulb lights will stop blinking. OK, if you do not touch both brakes, like I often do, the bulb light will stay steady lit even after you are underway and the ABS light has stopped blinking, until you do hit both of them.

As Lee said, without ABS the light should go out after you activate both brakes.

Now, I'm really confused. On my (fairly new to me)94 K1100LT ABS II, the brake lamp/switch warning lamp seems to have nothing to do with the ABS lamps. On mine, once it is started, both ABS indicators flash and the brake lamp/switch warning lamp comes on. If you then apply both brakes (either separately or together & you don't have to be moveing) the brake lamp/switch warning lamp goes out. Once you ride for a foot or so both ABS indicators stop flashing. If after starting it, you ride off without applying both brakes, then the brake lamp/switch warning lamp will stay on until you have applied both brakes. The above assumes that the tail lamp is good. Hope Im not confusing you all tooLater,,,De
 
Now, I'm really confused. On my (fairly new to me)94 K1100LT ABS II, the brake lamp/switch warning lamp seems to have nothing to do with the ABS lamps. On mine, once it is started, both ABS indicators flash and the brake lamp/switch warning lamp comes on. If you then apply both brakes (either separately or together & you don't have to be moveing) the brake lamp/switch warning lamp goes out. Once you ride for a foot or so both ABS indicators stop flashing. If after starting it, you ride off without applying both brakes, then the brake lamp/switch warning lamp will stay on until you have applied both brakes. The above assumes that the tail lamp is good. Hope Im not confusing you all tooLater,,,De

ABS on the K75 is totally different than ABSII on a K1100
 
Yes, clarification made :)

I meant to say when I went from the ABS-II K11 to the ABS-I K75RT I was confused because the two behave differently. I made a change in my post ("ABS-I") to clarify.
 
Thanks, guys-confusion cleared. My ÔÇÿ94K1100LT ABS II had been sitting for 2 years before I bought it a few months ago w/18K miles on it. Front brake master cylinder (leaking badly) and switch were beyond repair so I bought & installed new ones. There is no adjustment on the switch as it bolts on with 2 small screws. Everything worked as it should (I thought) as naturally I had checked that the switch worked fine. Most of the time the brake warning light would reset when I applied the rear brake only & rarely did I have to also apply the front brake to reset the light. On a recent ride a friend noticed that the brake light was on most of the time. Yep, even though the front brake leaver was returning all the way back to the stop, the brake light switch wasnÔÇÖt always being activated. I had to bend the switch leaver slightly so it would always be depressed fully and it all works as it should now.
Thanks again,,, De
 
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