Honda Rebel Forum banner
  • Hey everyone! Enter your ride HERE to be a part of November's Ride of the Month Challenge!
1 - 18 of 18 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter · #1 ·
The tail light on my Honda 250 Rebel only works when the key is turned to park. No brake light or tail light when its on. New bulb, new fuse.
Recently cleaned the carb, did I maybe upset a wire? If so can someone help me troubleshoot which one.
 

·
Premium Member
85 CMX 250C, 82 GW Remember that you are invisible, treat all others accordingly. Avoids Road RAGE!
Joined
·
1,609 Posts
Do the turn signals work when the key is on? What year is your Rebel? I don't see it in your signature line. Assuming 1st generation because 2nd generation often did not have park position.
The fuse holder (glass fuses) often gets corroded on the 1st Gen. I'd try cleaning that. I'll add the word 'carefully' because the brass becomes brittle with age. Mine broke whilst driving on the freeway shortly after "fixing" the same problem. I had to do an emergency repair at night. Not fun. Use some automotive bulb grease on them to prevent further deterioration.
 

·
Super Moderator
Joined
·
31,147 Posts
Welcome to the forum. Cleaning the carb shouldn't have disturbed any of the wiring, but it is suspicious the problem appeared after replacing the bulb and fuse. Just for the heck of it, I'd suggest testing the bulb to be sure both filaments work.
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #4 ·
Do the turn signals work when the key is on? What year is your Rebel? I don't see it in your signature line. Assuming 1st generation because 2nd generation often did not have park position.
The fuse holder (glass fuses) often gets corroded on the 1st Gen. I'd try cleaning that. I'll add the word 'carefully' because the brass becomes brittle with age. Mine broke whilst driving on the freeway shortly after "fixing" the same problem. I had to do an emergency repair at night. Not fun. Use some automotive bulb grease on them to prevent further deterioration.
My bike is a 1984. Yes, the turn signals work when the key is on.
I used a test light on the connections both at the light and the wires. At the light I'm only getting a ground light (green) but no power (red) light.
At the fuses:
When the bike is off I get a power light on the main and nothing on head or tail. When the bike is on they are all red.
Is this useful to diagnosing the problem?
 

·
Premium Member
85 CMX 250C, 82 GW Remember that you are invisible, treat all others accordingly. Avoids Road RAGE!
Joined
·
1,609 Posts
A fuse can look good and still be blown. With the fuse pulled, is there power on one side of the fuse holder for fuse #1 (bottom fuse)? Did you test for power through the fuse?
This is the fuse that feeds the taillights when the ignition is in it's normal on position.
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #6 ·
A fuse can look good and still be blown. With the fuse pulled, is there power on one side of the fuse holder for fuse #1 (bottom fuse)? Did you test for power through the fuse?
This is the fuse that feeds the taillights when the ignition is in it's normal on position.
There is a ground light when I use the test light on the fuse holder. Continuity of the fuse is good.
 

·
Premium Member
85 CMX 250C, 82 GW Remember that you are invisible, treat all others accordingly. Avoids Road RAGE!
Joined
·
1,609 Posts
When ignition is on, how is the voltage on the output side of the fuse?
 

·
Super Moderator
1987 CMX250C AC
Joined
·
2,569 Posts
84 CM250, Electrical wiring is very close to 1st generation 85-87 CMX250 Rebel.. They both have Park position on ignition switch..

With ignition On you should have power at both sides of taillight fuse..
Black supplies the fuse block Brown/Blue circuit > 8 prong/pin connector where it is changed to Brown/White > Speedo and Ignition switch..

The quickest test imo would be to see if there is power to speedometer back lighting with ignition On.. Brown/White circuit powers speedo internal lighting.. if speedo has illumination w/ignition On, than I would suspect dirty contacts within ignition switch preventing Brown/White from making contact to Brown tail light circuit..

We know the Parking circuit is good as Red battery is supplying Brown taillight circuit directly.

Product Schematic Rectangle Font Line
 
  • Like
Reactions: Emil

·
Premium Member
85 CMX 250C, 82 GW Remember that you are invisible, treat all others accordingly. Avoids Road RAGE!
Joined
·
1,609 Posts
Did you get it fixed? SoakedKarma has a color version of this diagram which is a little easier to follow.
 

·
Premium Member
85 CMX 250C, 82 GW Remember that you are invisible, treat all others accordingly. Avoids Road RAGE!
Joined
·
1,609 Posts
And belated welcome to the forum. We're here trying to help all whom we can.
 
  • Like
Reactions: Markrkolb

·
Super Moderator
1987 CMX250C AC
Joined
·
2,569 Posts
Did you get it fixed? SoakedKarma has a color version of this diagram which is a little easier to follow.
color version for 85-87 CMX250 Rebel is slightly different from B/W CM250 diagram I posted above.. 85-87 version lighting grounds are different and light socket pigtails are colored where CM250 indicates light socket wire pigtails are both black..
There may be other differences I haven't taken into account..

I'd forgotten I colorized the CM250 wire diagram a couple of years ago stashing it in another file folder.. So here you go!
Circuit component Schematic Rectangle Font Line
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #13 ·
color version for 85-87 CMX250 Rebel is slightly different from B/W CM250 diagram I posted above.. 85-87 version lighting grounds are different and light socket pigtails are colored where CM250 indicates light socket wire pigtails are both black..
There may be other differences I haven't taken into account..

I'd forgotten I colorized the CM250 wire diagram a couple of years ago stashing it in another file folder.. So here you go!
View attachment 111863
Wow thank you so much.
 

·
Premium Member
85 CMX 250C, 82 GW Remember that you are invisible, treat all others accordingly. Avoids Road RAGE!
Joined
·
1,609 Posts
Looking at the diagram, there are only a four areas where the problem could be. The ignition switch, the fuse holder, or the brown/white & brown/blue wires & their connections. Everything else has been verified as already working. Should simplify the search.
 

·
Super Moderator
1987 CMX250C AC
Joined
·
2,569 Posts
It's always wise to disconnect the battery negative cable any time you work on electrical system..
 
  • Like
Reactions: rickybug

·
Super Moderator
1987 CMX250C AC
Joined
·
2,569 Posts
you might find pencil eraser just the ticket to clean oxidation and buff the surface.
 

·
Premium Member
85 CMX 250C, 82 GW Remember that you are invisible, treat all others accordingly. Avoids Road RAGE!
Joined
·
1,609 Posts
Eraser yes, but be extremely careful not to flex the brass sides too much, they will crack as mine did. Then fail later while driving. Like I said before, not good to happen at 10 p.m.
 
1 - 18 of 18 Posts
Top