need answer to question on 90 venture

[Grey beard]

90 venture high beam will not work. when hi beam switch is pressed, the headlight lamp on dash lites up, and the entire dash dims. Checked the headlight bulb and it is good.

 

Where do we go from here? Could it be the switch itself? Its my cousin's bike, and he's trying to get it registered in San Antonio. Bought the bike in Indiana, and it was delivered to him.

 

Thanks for any help/advice in solving this issue.

 

If anyone lives near Mico Texas, and can help that would be cool.

 

Its his first bike, so he's a bit at a loss here.

[dingy]

90 venture high beam will not work. when hi beam switch is pressed, the headlight lamp on dash lites up, and the entire dash dims. Checked the headlight bulb and it is good.

 

Where do we go from here? Could it be the switch itself? Its my cousin's bike, and he's trying to get it registered in San Antonio. Bought the bike in Indiana, and it was delivered to him.

 

Thanks for any help/advice in solving this issue.

 

If anyone lives near Mico Texas, and can help that would be cool.

 

Its his first bike, so he's a bit at a loss here.

 

 

With the head light disconnected, does the dash still dim?

 

If it does there is a fair chance it is the CMU unit.

 

That is the dash display that shows fuel level, and other warnings. There is a thread on here about resoldering the connections in it.

 

http://www.venturerider.org/forum/showthread.php?t=33328

 

This thread detailed the unit out of an 83 bike which is somewhat different from the 90 model.

 

Same procedure overall though.

 

Also here is a thread to a schematic for the bike.

 

90-93 Yamaha Venture DA Wiring Diagram Rev C.pdf

 

I could suggest a method to verify the wiring coming out of the CMU unit. It would require your getting access to the area behind the headlight. I don't have a 90 model, the fairing is somewhat different from my 83.

 

Once you get access to the backside of the speedometer head, disconnect the smaller of the two white connectors that plug into the center of the head.

 

You will see one of the wires in the connector is a Green wire with a red tracer. This is the low beam circuit output. Another wire is a yellow wire with a green tracer. This is the High beam circuit output.

 

If you jumper positive battery on the Green wire with a red tracer the low beam should light up.

 

If you jumper positive battery on the yellow wire with a green tracer the high beam should light up.

 

If both of these work, then the problem may be in the CMU.

 

Next thing to check would be the connections at the left handle bar switch, and then inside switch itself.

 

Here is a thread on cleaning this switch.

 

http://www.venturerider.org/forum/showthread.php?t=42721

 

Let us know if any of this helps or not and we can suggest further steps.

 

Gary

Edited January 31, 2010 by dingy
corrected grammer

[MiCarl]

Sounds like possibly two separate problems.

 

The motorcycle has a device called a "reserve lighting unit". It's purpose is to keep the motorcycle from going dark if one of the headlight filaments burns out.

 

If you are on low beam and the low beam element goes out the RLU should switch on the high beam element and light the indicator to tell you of a bulb failure. Alternatively if you are on high beam and the high beam element fails it's supposed to switch to low beam and light the indicator.

 

The owners manual does not say what the RLU does if it gets neither the high or low beam from the handlebar switch. I suppose it's possible that it lights the indicator to let the operator know that neither beam is switched on. Personally, I'd suspect that or a problem with the RLU itself.

 

The extra load when the headlamp indicator is on is dimming your other lights. It's possible you have a poor connection somewhere that is giving extra resistance or it may be normal.

[dingy]

Sounds like possibly two separate problems.

 

The motorcycle has a device called a "reserve lighting unit". It's purpose is to keep the motorcycle from going dark if one of the headlight filaments burns out.

 

If you are on low beam and the low beam element goes out the RLU should switch on the high beam element and light the indicator to tell you of a bulb failure. Alternatively if you are on high beam and the high beam element fails it's supposed to switch to low beam and light the indicator.

 

The owners manual does not say what the RLU does if it gets neither the high or low beam from the handlebar switch. I suppose it's possible that it lights the indicator to let the operator know that neither beam is switched on. Personally, I'd suspect that or a problem with the RLU itself.

 

The extra load when the headlamp indicator is on is dimming your other lights. It's possible you have a poor connection somewhere that is giving extra resistance or it may be normal.

 

If he applies the jumpers & still gets the dimming it could be the RLU.

 

Possible check would then be to disconnect RLU & try jumpers again.

 

Gary

[Grey beard]

Thanks guys, you are awesome. I'm in Indiana and my cousin and bike are in San Antonio, so it may be a while to get some answers to and from him. This is a start.

 

We did have time to tear into the thing before I had to head home last week. We did check the solder issue on the dash display module, but found nothing obvious there. It may well be the switch itself. If I recall, the PO said that he had applied 12v from battery to hi beam side of lamp and it lit up. Must be something electrical in between lamp and switch.

 

I'll try to keep ya posted on progress, if any. My cousin is a neophyte at biking, and it is his first one. This should keep him busy for a while.

 

Thanks again.

[dingy]

Thanks guys, you are awesome. I'm in Indiana and my cousin and bike are in San Antonio, so it may be a while to get some answers to and from him. This is a start.

 

We did have time to tear into the thing before I had to head home last week. We did check the solder issue on the dash display module, but found nothing obvious there. It may well be the switch itself. If I recall, the PO said that he had applied 12v from battery to hi beam side of lamp and it lit up. Must be something electrical in between lamp and switch.

 

I'll try to keep ya posted on progress, if any. My cousin is a neophyte at biking, and it is his first one. This should keep him busy for a while.

 

Thanks again.

 

I would be cautious about applying 12 volts to headlight without disconnecting the connector on the CMU that I pointed out in previous post to this thread.

 

The headlight system puts an input voltage into the CMU on one set of wires then the CMU puts out a 12 volts to the headlight on another set of wires.

 

I don't know what the effect of putting 12 volts on the output side of the CMU would be.

 

Maybe nothing, maybe a new CMU.

 

Gary