general question on solenoid

[franksquires]

Does anyone know what the solenoid on the left side of the battery is for. When I hit my start button I believe there is a clicking sound that comes from it. My starter solenoid works, on the right side of the batt. if I jump it. Wondering if and how these two are connected.

[franksquires]

sorry I wasn't very clear at all on this. I am talking on a 88 1500 interstate there is a solenoid just left of the battery and one right which is the starter. My electric switch on the handlebar doesn't work but I can jump it across on the right solenoid and it will run. When I push the start button it sounds like the one on the left clicks. Any ideas?

[virgilmobile]

Just to be clear.To crank the engine,you are jumping the big terminals on the right solenoid.
Not pushing the start button at the same time or anything else but the key on.
Is this correct?

[virgilmobile]

One more question.After the bike is running,does the reverse work?
Those 2 solenoids operate start and reverse.

[virgilmobile]

On the 88,both relay(solenoid) A and B must "click" to pass power to the starter motor..
For reverse,only one is operated..
I don't have a very clear picture i can post but the first test is to probe the two wires that operate the solenoid..At one,there's a green/red and yellow/red...the other has black/red and yellow red..
With a DVM attached to each set,there should be 12 volts to make it click..
One solenoid..the one that clicks should have this volts when the button is pushed...check the other one...If there is no volts,we'll figure out the next step.

[ct1500]

The 88-89 GW's have the two post starter. Starter relay A to the right of battery provides voltage to one post and relay B to the left of battery provides the path to ground from the other post for the starter to operate.

[virgilmobile]

And for reverse,only one is used..a resistor network provides the ground for a slower motor operation.The second solenoid is not energized.

[franksquires]

Thanks guys for the input. So now here is the deal, the starter does not work at the button and I do not know about reverse because the bike is in disrepair, the way I bought it. The mechanic I bought it from suggested replacing the entire wiring harness which I am prepared to do but would rather not. I have bought a used handlebar set-up on ebay and plugged it in at the right fairing block but same deal, oh yeah and sorry to mislead you but it is the main relay that clicks not the solenoid. The bike starts with the key on and jumping the two big posts on solenoid A (right side). Also I was told by the mechanic the cruise control didn't work either. He said all voltages checked out at the switch itself (starter) and thought it was a resistor somewhere in the main harness, thus the replacement. I think I am a glutton for punishment but only paid 500 for the bike. I love the style and the little I have ridden it (just up and down the street) am sure once I get the carbs and wiring straightened out will provide me with a ton of fun. Thanks for any suggestions you may have

[franksquires]

I just went and tested voltage at solenoid A. The heavy red wire is is @ 12.3 full batt. voltage, the Brown wire when the start button is pushed Is 3.8 volts, and the yellow, when the button is pushed is 11.4. Does this help?

[virgilmobile]

Check the other solenoid too please.
We need to know what voltages are on the solenoid wires when the start button is pushed.Not so much the big ones,the small ones that make the solenoid click on.
Don't just replace the harness.You may simply have a bad diode or switch.

[franksquires]

Thanks Virgil there is no power anywhere at the solenoid B, orange o, green 0 yellow 0. This is both with the button pushed and just with key on.

[virgilmobile]

Thanks,Ill be at the schematic right after work today.

[franksquires]

Thanks I work late tonight so probably won't be able to reply til tomorrow. Many thanks....Frank

[virgilmobile]

While in thinking...The solenoids you talk about..."A" is on the right of the battery..."B" is on the left..
Does "A" click when you push the start button.?
What did you do to crank the bike...What terminals did you short together
Also,look above the solenoids..there should be a fuse holder near each one..they have a 5 amp fuse.Check them...
One more test too..The "A" solenoid has battery volts on it..the big cable...If it's the one that clicks,does the other big lug get 12 volts on it.?It actually provides power to make the other solenoid "B" click.Through the 5 amp fuse and a diode and the reverse switch...Not the switch in the front of the engine(neutral safety)..the one on the right side by the reverse mechanism.
I'll try to compile a schematic of the circuit this evening.

[virgilmobile]

More questions..You mentioned its on a state of disrepair.
Can you confirm if the neutral lamp is working.?
Have you tried to crank it by pulling in the clutch lever?

[franksquires]

The neutral light works but I haven't tried to start it with the clutch pulled in, will do that when I get home. Also dont know if it matters but the R light also temporarily comes on when I turn on ignition.

[virgilmobile]

Thanks for the info..the momentary lamp is a self test..I have a very good schematic...
I'll mark points of Interest.
there's 3 separate circuits that must work to get it to crank...The A solenoid must click..the relay under the seat must click and then the B solenoid completes the circuit.
red dots then green then yellow..

if the relay under the seat clicks,the A solenoid also should click...it sends 12 volts to the circuit for the B solenoid.

[virgilmobile]

By the way..3.8 volts on the brown wire of A solenoid...too much...it's the ground circuit for the solenoid...I'd expect to see no more than 0.8 volts...Swap that little relay out.Its either the relay contacts or the diode to the neutral switch...You could pull in the clutch lever and remeasure that volts again..if it drops to less than a volt,the neutral lamp diode is bad..if it stays up the relay contacts are bad..

[franksquires]

You have to be the 1500 guru for sure. Probably saved many wings from the graveyard. I just got home and it is late but the info you give me sounds a lot like what the mechanic I bought the bike from. Difference is he didn't have any specifics, hence replace the entire wiring harness. I will try out your suggestions first chance I get. by the way the only clicking I hear comes from the main relay in the fuse box on the left of the bike, no sounds from solenoids. Yes I can start it by jumping the two lugs on solenoid A

[virgilmobile]

Going by the schematic...
The relay you hear clicking is the main relay...That's normal..
With the key on,when you push the start button,it should provide 12 volts to the start solenoid "A"....You mention that its OK so the start button is working....
It also provides volts to the "reverse relay switch"(relay)..I believe it's under the seat toward the trunk....
It should click...it gets it's ground through the reverse switch and a diode.
When it clicks,it provides the "A" solenoid a ground through it's contacts,then a diode and either the neutral switch or clutch switch..
Now...The fact that it will crank by jumping the main terminals proves that the 5 amp fuse,Solenoid "B",reverse switch and one of the diodes is working..(the yellow pathway).
All of this information leads me to just a couple of possibilities (other than a broken wire or corroded connector)..
Reverse relay switch bad..
Diode bad..there's 3 of them to test.
Starter solenoid "A" bad..
Before you jump,attempt to start it when pulling in the clutch lever...I'm not positive why there's 3.8 volts on that one solenoid wire...Either the diodes,neutral switch or relay can cause this...
I suppose if you wanted to test...You could hitch a wire from the "A" solenoid to the battery ground...You know..the one that goes to 3.8 volts...Push the start button...See if the "A" solenoid clicks and cranks it...That would eliminate it as a problem and you can concentrate on the little relay and it's parts..
Keep us posted.

[franksquires]

Getting a bit confused with the relay, diode, and switch terminology. Don't get me wrong I am very appreciative for the education. I jumped a ground from battery to the brown wire at solenoid A and it did make it click, but not start. No cranking of starter. Can you explain the relay, and a diode a bit more for me please. Is a relay a junction where two sets of wires plug together with connectors in the harness or is it an identifiable electronic piece, say black plastic box that plugs into a terminal block? And the diode..my image is of a transistor looking electronic device found on a circuit board...hope this isn't to much. I really appreciate the info and help. Love doing the work but just don't have the experience to figure it out. With your help and guidance I think we can fix this problem. Thanks by the way nothing else clicke but the main relay in block and solenoid A when I jumped brown wire with ground from batt

[virgilmobile]

The relay is a small box.About 1x1x1.5 inch with a plug and 4 wires on it.A diode is about .5x.5x1 inch.2 contacts on it.
If the solenoid A clicked when you used the temporary ground (I hope it clicked only when you pushed the start button) but did not crank,that solenoid is bad.
You also proved that the relay circuit is not working either.
Attack it first.Locate it and measure the volts when you push the start button.One should goto 12 volts,all the rest should drop to less than 1 volt.

[virgilmobile]

A relay and solenoid are about the same.there both switches.energize the coil and it clicks the contacts closed,just like your light switch.the relays handle small power,the start solenoid is big power

[franksquires]

is it the relay for the reverse switch I need to test?

[virgilmobile]

Yup.Its needed to operate to get the start solenoid to click without using the temporary ground wire