headlight wiring

[barend]

The low beam on my '83 was dim and according to most all that would have related to the computer. Shop figured it was a relay. As it turns ou it they ound a burned wire in the harness. Unfortunatey the new wire run bypasses the computer, which means my warning light stays on:headache: Two options, cut out the warning: how? :confused24:or re-wire again and this time do it right, but I am not that technical:confused:

An advice would be welcome.

 

Of course my wife says I should get a new bike:big-grin-emoticon:

[Venturous Randy]

I bet you ten bucks to a donut that the problem is in your CMS and the only way to fix the problem is to take the CMS out and resolder the cold solder joints. It is a relative easy fix and everything will work like it is supposed to work. Just out of curosity, what did the shop charge you to do the by-pass wire? If you are interested in doing it right, just let us know and I am sure there are several of us on here that will give you a hand.

I just looked at your profile and with your adding lights like you did, you would find the CMS fix easy.

RandyA

[Gearhead]

I don't think the headlight circuit has any relays. It should...and mine does now...but stock, I'm pretty sure there are none. Therefore, all 5 amps go thru the key switch, the dimmer switch, the start button, as well as the RLU (reserve lighting unit). Cleaning those switches is the first thing to do in the case of low headlight voltage.

 

If you bypass the RLU, it triggers the CMS for a bad light. (The RLU must sense H/L current. Ask me how I know this...) If there was a bad wire, why did the shop bypass the RLU / CMS system? Why not just replace the bad wire run?

 

If I knew how to cut out the RLU without triggering that dadgum dash display, I probably would have, but I don't know how!

 

Jeremy

[GeorgeS]

Due to the Warning circuits installed. If the Circuit Borard with the Warning Senceing Components Fails, you could loose your Low Beam on the Road.

 

SO:

 

I Installed a Complete New circuit. A DPDT Switch.

 

---One side of this switch OPENS the Stock circuit -- TO --- the Low Beam on the Bulb.

 

--- The Second set of contacts, Takes Voltage From, a New Fuse, thru the new switch, To the Low Beam Contacts.

 

In other words, if the OEM Circuit Fails, I simply Throw the Switch, and My Low Beam is Powered from a Competly Seperate, Fused, Circuit.

 

 

Also, I have noted, that in the " Bypass " mode, the Low Beam is noticable Brighter. Apparently there is some Voltage Drop across the Warning Sensor Circuits.

 

Next time I open the Instrument panel, I'm going to try to figure out How to Disable the Headlight Warning Circuit.

 

I realize that the " electricaly challanged " will have trouble with this, but the electrical guru's out there won't !! and should be able to help the others.

 

I have never actually had to use it on the road, But, Its there if I need it.

 

[barend]

To answer some questions; I told the shop about this site and gave them the address and the likely cause that many of you have found (the CMS). Also told them the tech manuals are on line plus i handed them my Service Manual. As far as why or how they bypassed the RSL or the CMS, don't know! they certainly had access to the right information.

I paid them $195; this included lubricating the speedo cable and odometer, 'cause that thing started screaming like a banshee. The invoice does not specify a charge for the relay but does list 4 fuses.

 

Being self employed I tend to weigh my time (loss of revenue) vs. shop costs, so although I may well be able to fix this myself, it may take me more time then I am willing to invest.

Having said that, I was rather put out by the fact that this seems to be more a patch then a repair AND their re-assembly left my choke inaccessible, my clutch lever pointing the wrong way and the tank fairing flopping around. Whether their work aggravated the operation of the other sensor lights (brakes, oil and fuel) would be anyones guess.

i.e. I am lookin at trying to figure this out myself

[Gearhead]

"Figure it out" being the key phrase. The shop likely didn't take any more time than necessary and probably doesn't understand the RLU / CMS system at all.

 

Jeremy

[timgray]

Next time I open the Instrument panel, I'm going to try to figure out How to Disable the Headlight Warning Circuit.

 

I realize that the " electricaly challanged " will have trouble with this, but the electrical guru's out there won't !! and should be able to help the others.

 

I have never actually had to use it on the road, But, Its there if I need it.

 

 

On the CMU board if you follow where the headlight wires go they go through a coil of wire that wraps around a a glass device. That glass device is a "reed" switch, They close in presence of a magnetic field. The coil makes a magnetic field when the headlight is working. if you short that glass device the CMS thinks that the headlight is still working and happy.

 

The same setup is used for the brake lights as well. I was hoping to find a pinout of the CMS unit so I could write up a document on how to bypass alerts and other problems.

 

If anyone has a DEAD CMS I'd be willing to disect it further to get more information for everyone about it's operation.

[GeorgeS]

On the CMU board if you follow where the headlight wires go they go through a coil of wire that wraps around a a glass device. That glass device is a "reed" switch, They close in presence of a magnetic field. The coil makes a magnetic field when the headlight is working. if you short that glass device the CMS thinks that the headlight is still working and happy.

 

The same setup is used for the brake lights as well. I was hoping to find a pinout of the CMS unit so I could write up a document on how to bypass alerts and other problems.

 

If anyone has a DEAD CMS I'd be willing to disect it further to get more information for everyone about it's operation.

 

Thanks for that information !!! Most appreciated, its on my to do list.

[Gearhead]

How interesting! Up until now the CMS has just been a magic black box. Thanks.

 

Jeremy