Planet Minis

orangekoi · 07-05-2009, 07:23 PM

I have a potential buyer lined up for my ct70, but after tuning it up, getting a new battery, and having a great time buzzing around on it, I've realized that the turn signals and the brake light do not work.

The tail light works, but when the brake is depressed, the light goes out. When the horn is sounding and the turn signals is turned on, the horn goes out.

Does this sound like a short or might there be another explanation?

I'm considering buying a new wiring harness and seeing if this resolves the issue. Anyone have any experience installing a new harness? Difficulty?

Thanks for any advice!

Henry

Blackwoodz · 07-05-2009, 07:59 PM

Bad ground.....

orangekoi · 07-06-2009, 04:50 PM

Thanks Blackwoodz. I went and cleaned the ground connection under the tail light. Didn't fix the issue. Other suggestions are appreciated.

I've found a new wiring harness here: MAIN WIRE HARNESS CT70 K3_TO_1976 (267V)

$33 isn't bad. Anyone know if there is much to installing one of these? I'm guessing that if there is a short somewhere off of the main harness, this will not fix the issue.

I need to sell this bike and the guy I have lined up right now is definitely interested. Don't know if the electrical issue is a deal breaker, but I'd like to sell this thing completely street legal. Any further help is much appreciated.

FastMC · 07-06-2009, 05:27 PM

Quote:

Originally Posted by orangekoi

Thanks Blackwoodz. I went and cleaned the ground connection under the tail light. Didn't fix the issue. Other suggestions are appreciated.

I've found a new wiring harness here: MAIN WIRE HARNESS CT70 K3_TO_1976 (267V)

$33 isn't bad. Anyone know if there is much to installing one of these? I'm guessing that if there is a short somewhere off of the main harness, this will not fix the issue.

I need to sell this bike and the guy I have lined up right now is definitely interested. Don't know if the electrical issue is a deal breaker, but I'd like to sell this thing completely street legal. Any further help is much appreciated.

Could be a short to ground somewhere. Could also just be a lack of nec. current to run all that stuff. You didnt mention your headlight working or not...Does it get brighter when you rev the motor ? That will at least tell you if your AC generator is working. If you have a multimeter, test the voltage at the battery then start and rev the motor to check the charging circuit. Also see what happens to the voltage when you press the brake, beep the horn etc.
If you replace the harness buy it here: Honda Trail Bikes
You'll have to remove the tank from the frame to access all the connections.

orangekoi · 07-17-2009, 04:46 PM

Well guys,

I spent a couple hours today and replaced the main wiring harness in my ct. Everything went smoothly. Tank came out without any issue. Wiring harness was easier to install than I expected. A couple of tight spots, but nothing too bad.

Bad news is that my electrical issues is not resolved. The electricals on the bike act the same way they did before. Only good thing that came out of today was the realization that there isn't a short in the harness.

Here's the symptoms again. The turn signals do not turn on whatsoever. The brake light does not turn on. The headlight (hi and lo) does work as does the tail light. The horn works too. When the brakes are engaged, the taillight goes out. When the turns signals are switched on, the horn will no longer work.

The headlight does brighten when the engine is revved. I have a new 6v battery installed.

Any ideas or suggestions are much appreciated.

Henry

Blackwoodz · 07-17-2009, 04:59 PM

It still sounds like a grounding or lack of good grounding issue to me....did you replace the voltage regulator or stator?

orangekoi · 07-17-2009, 05:01 PM

Blackwoodz,

Is there another ground other than the one under the rear fender? Would you suggest more than cleaning off the corrosion and making sure there is good metal to metal contact?

Haven't replaced the stator or regulator yet.

Blackwoodz · 07-17-2009, 05:07 PM

I do not know that bike or its electical schematics.... but I just know how the lack of a good ground acts.
Sorry I can not be more helpful. Fast MC should be able to give you a detailed layout since I know I have seen his posting of retro fitting that harness in his bike. You really should check the voltage output of your stator at the regulator.

nielspbr · 07-17-2009, 05:10 PM

Stupid question, is the fuse Ok?

makotosun · 07-17-2009, 05:27 PM

Definitely sounds like a grounding issue. The keyswitch needs to be grounded (nice and tight) too.

Another thought is to make sure that the bulb is actually good

Pull it out and connect both poles and make sure you don't have a burned filament. Happened to me . . .

HymieP · 07-17-2009, 08:46 PM

I agree with above posts, sounds almost identical to my problem which was at the ignition and the rear tailight area. Check and double-check, these bikes aren't complicated, you'll find it if you keep digging. Good luck

schofell84 · 07-17-2009, 09:26 PM

check the switches on the handlebars, clean them up and use some dielectric on them. it def. sounds like a ground issue though haha.

cdoublejj · 07-18-2009, 01:39 AM

there should be multiple ground spots and yeah i was thinking the one of the 2 filaments in the tail light might be burnt.

07-05-2009, 07:23 PM	#1 (permalink)
orangekoi PM Newbie Join Date: Jul 2009 Posts: 4	1976 CT70 Electrical Issue I have a potential buyer lined up for my ct70, but after tuning it up, getting a new battery, and having a great time buzzing around on it, I've realized that the turn signals and the brake light do not work. The tail light works, but when the brake is depressed, the light goes out. When the horn is sounding and the turn signals is turned on, the horn goes out. Does this sound like a short or might there be another explanation? I'm considering buying a new wiring harness and seeing if this resolves the issue. Anyone have any experience installing a new harness? Difficulty? Thanks for any advice! Henry

07-05-2009, 07:59 PM	#2 (permalink)
Blackwoodz 3rd Gear Member Join Date: Aug 2008 Location: SC Michigan Posts: 3,624	Re: 1976 CT70 Electrical Issue Bad ground.....

07-06-2009, 04:50 PM	#3 (permalink)
orangekoi PM Newbie Join Date: Jul 2009 Posts: 4	Re: 1976 CT70 Electrical Issue Thanks Blackwoodz. I went and cleaned the ground connection under the tail light. Didn't fix the issue. Other suggestions are appreciated. I've found a new wiring harness here: MAIN WIRE HARNESS CT70 K3_TO_1976 (267V) $33 isn't bad. Anyone know if there is much to installing one of these? I'm guessing that if there is a short somewhere off of the main harness, this will not fix the issue. I need to sell this bike and the guy I have lined up right now is definitely interested. Don't know if the electrical issue is a deal breaker, but I'd like to sell this thing completely street legal. Any further help is much appreciated.

07-17-2009, 04:46 PM	#5 (permalink)
orangekoi PM Newbie Join Date: Jul 2009 Posts: 4	Re: 1976 CT70 Electrical Issue Well guys, I spent a couple hours today and replaced the main wiring harness in my ct. Everything went smoothly. Tank came out without any issue. Wiring harness was easier to install than I expected. A couple of tight spots, but nothing too bad. Bad news is that my electrical issues is not resolved. The electricals on the bike act the same way they did before. Only good thing that came out of today was the realization that there isn't a short in the harness. Here's the symptoms again. The turn signals do not turn on whatsoever. The brake light does not turn on. The headlight (hi and lo) does work as does the tail light. The horn works too. When the brakes are engaged, the taillight goes out. When the turns signals are switched on, the horn will no longer work. The headlight does brighten when the engine is revved. I have a new 6v battery installed. Any ideas or suggestions are much appreciated. Henry

07-17-2009, 04:59 PM	#6 (permalink)
Blackwoodz 3rd Gear Member Join Date: Aug 2008 Location: SC Michigan Posts: 3,624	Re: 1976 CT70 Electrical Issue It still sounds like a grounding or lack of good grounding issue to me....did you replace the voltage regulator or stator?

07-17-2009, 05:01 PM	#7 (permalink)
orangekoi PM Newbie Join Date: Jul 2009 Posts: 4	Re: 1976 CT70 Electrical Issue Blackwoodz, Is there another ground other than the one under the rear fender? Would you suggest more than cleaning off the corrosion and making sure there is good metal to metal contact? Haven't replaced the stator or regulator yet.

07-17-2009, 05:07 PM	#8 (permalink)
Blackwoodz 3rd Gear Member Join Date: Aug 2008 Location: SC Michigan Posts: 3,624	Re: 1976 CT70 Electrical Issue I do not know that bike or its electical schematics.... but I just know how the lack of a good ground acts. Sorry I can not be more helpful. Fast MC should be able to give you a detailed layout since I know I have seen his posting of retro fitting that harness in his bike. You really should check the voltage output of your stator at the regulator.

07-17-2009, 05:10 PM	#9 (permalink)
nielspbr Euro Seagull Join Date: Feb 2008 Location: Netherlands Posts: 463 My Mood:	Re: 1976 CT70 Electrical Issue Stupid question, is the fuse Ok?

07-17-2009, 05:27 PM	#10 (permalink)
makotosun 2nd Gear Member Join Date: Apr 2005 Location: Washington (southwest) Posts: 510 My Mood:	Re: 1976 CT70 Electrical Issue Definitely sounds like a grounding issue. The keyswitch needs to be grounded (nice and tight) too. Another thought is to make sure that the bulb is actually good Pull it out and connect both poles and make sure you don't have a burned filament. Happened to me . . .

07-17-2009, 08:46 PM	#11 (permalink)
HymieP 2nd Gear Member Join Date: May 2008 Location: Norman, OK Posts: 299	Re: 1976 CT70 Electrical Issue I agree with above posts, sounds almost identical to my problem which was at the ignition and the rear tailight area. Check and double-check, these bikes aren't complicated, you'll find it if you keep digging. Good luck

07-17-2009, 09:26 PM	#12 (permalink)
schofell84 2nd Gear Member Join Date: Feb 2007 Location: Ogdensburg Posts: 277	Re: 1976 CT70 Electrical Issue check the switches on the handlebars, clean them up and use some dielectric on them. it def. sounds like a ground issue though haha.

07-18-2009, 01:39 AM	#13 (permalink)
cdoublejj 3rd Gear Member Join Date: Oct 2008 Location: St.Joe MO Posts: 1,367 My Mood:	Re: 1976 CT70 Electrical Issue there should be multiple ground spots and yeah i was thinking the one of the 2 filaments in the tail light might be burnt.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)