Total electrical failure after pressing starter button on R1100RT

[JimmR75]

I have a '97 R1100RT that I bought out of an estate that I am working to put back on the road.  It had sat for ~10 years before I acquired it and it was not properly prepared for storage.  

I have done the normal services including oil and filter, new plugs, valve adjustment, cleaned injectors (not professionally), and cleaned BBS's.  I have also had the fuel pump and filter replaced (Reto).

I have gotten it running but am experiencing an unusal electrical issue.  When I turn the key on I get all the normal dash lights.  Intermittenly, when I press the starter button the starter will engage for a second and then all the electrics will go dead (all lights, RID, etc.).  If I turn the key off and cycle it back on, everything will power back up normally (most of the time).  If I continue this sequence it will eventually crank the engine normally and start up.  It may take five or more repeated attempts before things work normally.

Is there a relay or other point in the electrical system that could kill everything (unload relay?).  

The battery is brand new and voltage tests OK>

 

 

[dirtrider]

33 minutes ago, JimmR75 said:

I have a '97 R1100RT that I bought out of an estate that I am working to put back on the road.  It had sat for ~10 years before I acquired it and it was not properly prepared for storage.  

I have done the normal services including oil and filter, new plugs, valve adjustment, cleaned injectors (not professionally), and cleaned BBS's.  I have also had the fuel pump and filter replaced (Reto).

I have gotten it running but am experiencing an unusal electrical issue.  When I turn the key on I get all the normal dash lights.  Intermittenly, when I press the starter button the starter will engage for a second and then all the electrics will go dead (all lights, RID, etc.).  If I turn the key off and cycle it back on, everything will power back up normally (most of the time).  If I continue this sequence it will eventually crank the engine normally and start up.  It may take five or more repeated attempts before things work normally.

Is there a relay or other point in the electrical system that could kill everything (unload relay?).  

The battery is brand new and voltage tests OK>

 

 

Afternoon JimmR75

 

No real main relay or complete disconnect, there is a load shed (load relief) relay that shuts off accessories  lights, etc during engine cranking. (actually it shuts the lights &  accessories off during starter button push)

 

Your problem probably needs a little more attention to WHAT actually quits during starting attempt.

 

It sort of sounds like the load shed relay is working correctly & shutting things off during (attempted) engine cranking  but the starter itself isn't always powering up.  

 

The black wire going to the starter solenoid is the part of the circuit that shuts the load shed relay off so if your problem is just the normal things turning off during engine cranking then it sounds like the starter solenoid is getting 12v B+ from the starter button but the starter itself is not actually cranking. 

 

If you want to try something then hook a remote starter switch between the large 12v B+ stud on the starter solenoid  & the smaller  terminal on the starter solenoid (unplug the black wire from that terminal) then see if it ALWAYS cranks when the remote switch is pushed. If it doesn't then you most likely have starter issues. 

 

If/when you unplug the black wire going to the starter solenoid with the key ON, IF, the exact same things turn off as when you try to unsuccessfully start it then that says the load shed relay is working correctly & de-powering the lights etc so that more points to a starter issue or a loose battery cable, or a high resistance battery cable ground (under the air box)  

[JimmR75]

I have more info and may have found the / a problem.  

I put a meter on the battery and turned the key on (14.4 volts indicated). 

I left it connected and when I hit the starter button it drops to less than 1V, everything shuts down, and stays there until I turn the key off.  

When I turn key off the voltage will return to normal in a few seconds.

I am not an electrician but my past experience with this indicates a battery problem (failure under load).  

My replacement battery may be bad. 

[Hosstage]

Are you measuring voltage directly at the battery posts, or thru the wiring?

If at the posts, it sure does seem a bad battery.

[dirtrider]

41 minutes ago, JimmR75 said:

I have more info and may have found the / a problem.  

I put a meter on the battery and turned the key on (14.4 volts indicated). 

I left it connected and when I hit the starter button it drops to less than 1V, everything shuts down, and stays there until I turn the key off.  

When I turn key off the voltage will return to normal in a few seconds.

I am not an electrician but my past experience with this indicates a battery problem (failure under load).  

My replacement battery may be bad. 

Afternoon JimmR75

 

Yes, that could be a bad battery or just a poor cable connection at one of the battery posts, or even at the engine negative cable ground side connection.  Have your battery load tested,  if OK then look for connection problems. Measure the voltage right on the battery posts themselves not the cables connected to the posts. 

 

You could also run a voltage drop test between the battery (actual battery posts) & engine. 

[JimmR75]

My suspicion of a bad battery was premature.  A replacement battery did not change the situation.

 

Battery terminal connections are solid, going to take a closer look at other connections.

 

Any suggestions are welcome. 

[dirtrider]

25 minutes ago, JimmR75 said:

My suspicion of a bad battery was premature.  A replacement battery did not change the situation.

 

Battery terminal connections are solid, going to take a closer look at other connections.

 

Any suggestions are welcome. 

Morning  JimmR75

 

Do a voltage drop test between the battery (-) post & the engine case. 

 

If that is OK then do a voltage drop test between the battery (+) post the starter big B+ stud & between the battery (+) post & the ignition switch red wire. 

 

One place of concern is the main system ground at rear of engine under the air box (a REAL PAIN to access). That tends to corrode the become high resistance. 

 

The other is the red or green wire running from the handlebars to the frame (usually near the retaining zip tie) . These tend to fracture over time & numerous handlebar motions.  Try moving the handlebars back & forth while you try starting it.  

 

I have also seen a few ignition switch failures (the switch contacts themselves) that act intermittently.   

 

Place to start is with the voltage drop measurements just to eliminate that area. 

 

If the voltage drops are OK then you will probably need to use a voltmeter or 12v test light & check each powered circuit branch at time of failure. 

 

It could also be something not related to the B+ side like a grounding issue or even the side stand switch causing a key circuit shutdown.