Tail lights and RLU question

Discuss everything about Honda GoldWing. Feel free to ask any question related to GoldWing.

Moderators: CYBORG, Oldewing, robin1731, Forum Moderators

Post Reply
pjlogue
Billet Alum. Member
Billet Alum. Member
Posts: 278
Joined: Thu Jun 07, 2018 8:30 am

Tail lights and RLU question

#1

Post by pjlogue »

I'm not familiar how the RLU unit is supposed to work. I have a low glow from the dash cluster bulb for the tail light. The rear running light element and the brake element are both glowing. When I hit the brake both elements brighten. Is this normal? Has anyone opened up the RLU to fix them?

My understanding is the dash light for the rear light should be off and come on when the brake is applied. If the dash light is on all the time it means the running light is not working. Both elements in the bulb work

Any suggestions would be appreciated.

Thanks,
-P.
User avatar
robin1731
Membership Admin
Membership Admin
Posts: 21724
Joined: Mon May 29, 2006 8:31 am
Location: Decatur, Indiana

Re: Tail lights and RLU question

#2

Post by robin1731 »

Most everyone eliminates/bypass the RLU. It causes too many issues.

.
1976 Goldwing Super Sport
1985 Honda Elite
1976 KZ900 Dragbike
1992 ZX7 Dragbike (KZ900 style motor w/NOS)
and a rotation of various purchases
Randakk approved Carb Rebuilder
User avatar
Sidecar Bob
Honored Life Member
Honored Life Member
Posts: 7633
Joined: Sun Jun 11, 2006 10:14 pm
Location: Kawartha Lakes, Ontario

Re: Tail lights and RLU question

#3

Post by Sidecar Bob »

Yep. Problems with them are so common Clymer included how to bypass it in the basic troubleshooting chapter.

The RLU is supposed to monitor current through the tail light's dim filament (marker light) and in the event of zero current flowing (filament burned out) it turns the bright filament on at half voltage while also turning on the light on the instrument panel to notify you that you need to replace the bulb.
It does the same for the headlight, supplying half voltage to the high beam in the event of low beam failure.

Later models didn't have them so I guess bypassing it could be considered an upgrade...
Mr. Honda ('83 GL1100/Dnepr) summer How a motorcycle evolves thread
The Famous Eccles ('84 CX650EI/VeloUral) winter Never Ending Build (CX500forum)
Click: Colour schematics for all GL1000 & GL1100 and GL1200 standard models plus instructions on how to download the full size version
"A guy with two sidecars can't be all bad." - Cookie
Another guy with two sidecars..... Hmmmm... must be something to that....
pjlogue
Billet Alum. Member
Billet Alum. Member
Posts: 278
Joined: Thu Jun 07, 2018 8:30 am

Re: Tail lights and RLU question

#4

Post by pjlogue »

Thank you for the replies. For the time being I'll do the jumpers to bypass the RLU. I would like to duplicate the circuit or fix the RLU. The potting epoxy the RLU is encased it kind of makes repair impossible. From what I can see, the heat sink inside the RLU is also encased in epoxy which kind of makes the heat sink pointless. That is probably the cause of failure on most of these units.

Thanks,
-P.
Shadowjack
Silver Member
Silver Member
Posts: 654
Joined: Fri May 26, 2017 11:07 am

Re: Tail lights and RLU question

#5

Post by Shadowjack »

Both elements glowing at once can be caused by the bulb being forced in backwards.
Post Reply
  • Similar Topics
    Replies
    Views
    Last post

Return to “GoldWing Tech Discussions”