Topic: electrical question on 550

[CapeCafe]

I refurbished the wiring harness on my 1976 CB550k.  I replaced the ground wire (GRN) from end to end and all the connectors.  I re-installed it and I'm thinking I may have a problem.  My concern is when I turn the ignition key to the 1st position I get:

headlights
turn signals
all idiots lights except signal light
front and rear brake light
starter
(no horn)
(no tach or speedo light)
(no tail light)

When I turn to the 2nd position, everything goes off and the tail light comes on (bright).

I have been following the wiring diagram for the CB550k and I seem to have power and continuity where it is supposed to be through the ignition.  I have never had the bike running and not sure if this is normal.  I tried to take great pains to make sure everything went back together the same way it came off.  The fact I don't have tail lights or instrument lights leads me to believe I messed up somewhere.  Any thoughts appreciated

[w1sa]

Are you sure all power and ground tails/connectors for those items are plugged in and clean/secure...? Also check condition of bulbs/sockets.
 
Using a multi-meter and checking against the wiring diagram, you should also prove the ground circuit  has continuity.....from the respective frame ground to/from and thru all connections for those items.
 

[dave500]

the parking lamps come on with the key in the second position,you can then remove the key,this is how its meant to work.

[LesterPiglet]

If you say your tail light comes on "bright" in the second position you have your brake and tail light connections reversed.

[CapeCafe]

Dave500- when you say parking lights, are you referring to just the tail light?  Or, should the rear/front signals be lit as well?  I am using a Lucas style tail light and have the black wire from the TL connected to the Brown wire that runs from ignition through the fuse box and ending at the tail light.  The Red wire from the TL is connected to the Grn/Y wire that is activated by the brake switches.  I have a ground wire connected to the TL and plugged directly into the end of the Gr harness ground wire.

When the ignition switch is in the 1st position I have power through the Grn/y wire to the TL when the brakes are engaged, but nothing on the Br wire until the ignition is switched to 2nd position.  I ran a continuity check on the ignition and have continuity in the 1st position between Red-Blk and then between Br-Br/wht.  In the 2nd position there is continuity between R-Br and that is what is lighting the TL (parking lights).  Since this is what the manual calls for; what am I missing?  Should the tail light be lit when the bike is running with the ignition in the first position?

Thanks for your responses and your thoughts are appreciated.

[CapeCafe]

Lester- i did re-check my TL bulb and it turns out I had it screwed in wrong where the dim side was not powering (just bright).  I have it now where the brake switch lights up the bright side, and when I turn the ignition to 2nd position the dim side lights for the parking light, Dave500 mentioned.  I'm still confused as to why the TL is not lit (dim side) when the HL is lit on ignition position 1.  Since I have never had a CB550 and this one was a box of parts when I recieved it, I'm just assuming the TL should be lit when the HL is on.  Is that a correct assumption?

[dave500]

i rarely post in electrical questions as i like to see it,naming colours is all very well so long as they havent been spliced and changed somewhere?the tail and front marker lamp should light when the key is in the second position.

[CapeCafe]

Understood.  So far the wiring harness has matched exactly to the CB550 wiring diagram in the service manual.  The confusing thing is that the grn/yel wire to the TL only allows power to the bulb when the switch is activated at either brake.  That is easy to see and test.  Everything works as designed.  The Brn wire is only powered when the key is in the second position.  Again, everything is fine and it works as designed.  The thing that is confusing, is the fact there is no power through the Brn when the key is in the first position, hence no lit TL when running.  I have done continuity checks on the ignition switch and everything works as designed.

The Brn wire has a female plug inside the headlamp bucket that the wiring diagram shows, but is not used.  My original harness has this Brn plug and it looks as if it's never been used.  I saw a thread on this subject that talked of jumping that Brn to a switched Black in order to power the TL when the HL is on in 1st position.  On a completely stock, unmolested 1976 CB550k, should the TL be lit when the HL is lit and the ignition is on (1st position)?  If so, that power must come from the Brn wire that runs directly from the ignition switch through the 5amp fuse to the TL but that wire only has power in 2nd position when connected to the Red (constant hot). 

[mono]

there is an unused wire in the headlight bucket (forget which color, though).  wiring is a PITA.  I'll be in my garage in about an hour and can pull the headlight to post a pic for you if ya want.

in the meantime, it may be a stupid suggestion but what about the fuses?

[CapeCafe]

Thanks.  Fuses are all good and have tested each connector for continuity and volts.  Again, all good.  I do have the Br wire end in the HL bucket that shows in the wiring diagram.  I'm going to make a jumper and connect it to the switched Blk so there is power to the TL in ignition 1. 

[CapeCafe]

When I jump the surplus Br plug wire in the HL bucket to Blk switch wire, the TL lights when the headlight is on.  Thats the good, the bad is the 5amp TL fuse blows when the ignition is switched to 2nd position.  Somthing is still wrong and I cannot figure out where.  It's not that complicated, but it does seems as if the TL is not meant to light in ignition position 1 since Brn is the power wire for the light.

[LesterPiglet]

The brown in the headlight is unused. If you need to use it something is amiss.

[bryanj]

The spare brown is for the front marker bulb fitted into the reflector in non US markets, I dont think the front running lights should light up in 2nd key position , only the rear light in the US.

It sounds like your lights on/off switch is either not working correctly or not wired correctly

[CapeCafe]

I'm going to do continuity test again on my left hand controls-HL, Blinker and Horn.  They bench tested fine after I refurbished them, but I am not getting continuity now through the light Blue switch wire to the horn.  Since the headlight switch is always on when the key is in first postion and the Black wire is hot, and I have Hi and Low beam, I don't see a connection to the tail light.  The only constant power to the tail light per the wiring diagram is the Brn wire out of the switch, and that wire is only hot when the ignition is in 2nd position and the Black switch wire is off.  The other tail light wire (Grn/Yellow) is only hot when the key is in the first position and either brake switch is activate to close the circut.

Am I totally missing somthing that powers the switched wire (grn/Yellow) absent either front or rear brake switches?  Or am I totally missing somthing that powers the Br wire absent the ignition switch being in the 2nd (park) position?

[w1sa]

If your bike is wired for HL auto on, then the TL should also illuminate at the same time......from the wiring diagram, the Br wire to the TL should therefore be live whenever the Main Switch is turned ON (Pos 1 or 2)....that's achieved by the switch mechanism having  two contacts for the Br TL wire/terminal, and only a single contact for each of the other two switched power terminals..........so, I would also suspect the main switch being faulty.....sometimes the internal switch contacts get worn/dirty/corroded etc.... the fact that the pos2 contact is apparently functional is possibly indicative that it is usually the least used/worn.....

[CapeCafe]

Thanks for the info.  I did run the ignition switch continuity test per the manual, and have continuity:

1st - Red to Black
       Brown to Br/White
2nd- Red to Brown

I think I am having a problem with the Br/White wire bringing power into the switch to power up the Brown wire in 1st position.  I see that the Black switched wire energizes the Br/White in 1st position.  Thanks.  Now I can track down the issue through the Br/White connections and see where it drops off.  Cheers

[MOONDOGNYC]

Have you sorted this out ? I have the same issue. I have not tailight on when running, but it comes on bright when levers are applied.

[dave500]

are you #$%*ting us moondogwhathes name?you have no tail light then it goes bright when levers,,like the brake levers are applied,,,#$%*ing jesus wept,,your tail light globe has blown,,but the brake light one is ok,replace the #$%*ing globe,is this #$%* real?

[bollingball]

are you #$%*ting us moondogwhathes name?you have no tail light then it goes bright when levers,,like the brake levers are applied,,,#$%*ing jesus wept,,your tail light globe has blown,,but the brake light one is ok,replace the #$%*ing globe,is this #$%* real?

Temper temper Dave before you know it your post count will drop
Ken

[bryanj]

Yeh but he' right!!!

[MOONDOGNYC]

Sorry... got it confused with another thread. I have the issue with the rear tail light disconnected. But thanks for your help...

[dave500]

ha!no worries moondog.

[MOONDOGNYC]

CapeCafe, I keep blowing the 5 amp fuse for the tail light and gauges also. I have the entire rear lights dosconnected and it still happens.  Same exact scenario... Turn the key, POP goes the fuse. Turn it all the way and the tail light lights up. Everything else works. Signals, horn headlight, brake light.
   I'm really interested in what you find/found.

[dave500]

i dig your avatar,,herman munster bending some notes?

[LesterPiglet]

That's Boris doing Frankie.