does bad starter relay = no lights/power when key is on? where am I going wrong?

[robinelwood]

I haven't found an answer via search function. I stare at the wiring diagram and It's probably obvious, but I don't know. Thanks for any insights!

1980 GS850. Good charging system health, (known good battery properly trickle charged. SH775 reg/rec, Installed a cheap voltemeter), Battery is recent, bike charges great.

. This started as on occasional issue, and now it's most of the time.

I switch the key on, and get nothing; no lights, no crank, no click. Stone cold nothing.

If I turn the key enough times, everything will randomly come on as usual: then the bike starts, everything is good until the next time.

When the key is on but nothing lights up, bridging the starter relay posts makes the starter spin fine, but seems there's no power to the ignition because it doesn't fire.

I've removed headlight bucket and gauges and cleaned connections coming from the ignition. I've run contact cleaner into the key slot and wiggled. I've knocked on the side of the starter relay with a piece of wood. I've removed and cleaned fuses and fuse holders.

WHAT AM I MISSING? Will a bad starter relay prevent all power, or is there another mystery box I should replace? Messing with the key/ignition doesn't seem to be helping.
Thank you so much,
Robin E in Bellingham, WA

 

[Cipher]

Remove ign. Switch and check internals.
be cautious.

 

[robinelwood]

What would bad internals look like? visible corrosion, or just bad spirits hiding in there?

 

[Cipher]

Corrosion worn contacts
I had one once in which the copper bits crumbled to dust

 

[Rob S.]

I don't think a bad starter relay would cause your 'lights out' condition (I have a bad starter/relay and everything else works - 11EZ).

Sounds like a loose/corroded/worn connection. You might check in the area of the steering stem, where movement of the handlebars can cause stress.

 

[rphillips]

Yep, starter relay effects only the starter, ign. switch affects most everything except the brake light.

 

[Brendan W]

If turning the key repeatedly changes things then the ign switch internals are the most likely suspect.
Dismantling and cleaning is a fairly straight forward job.
While you are in switch cleaning mode check the internals of the kill switch as well. It could be taking volts from your coil supply.
The pigtail plug on the fusebox is also worth a clean but these last two are probably nothing to do with your problem.

 

[robinelwood]

Thanks to all: that gives me a direction to go. Appreciate the good advice.

 

[bwringer]

If turning the key repeatedly changes things then the ign switch internals are the most likely suspect.
Dismantling and cleaning is a fairly straight forward job.
While you are in switch cleaning mode check the internals of the kill switch as well. It could be taking volts from your coil supply.
The pigtail plug on the fusebox is also worth a clean but these last two are probably nothing to do with your problem.

Agreed on all points.

You won't BELIEVE the crud you'll find down inside the switchy slidy bits of the ignition. I suspect that'll be the cure.

 

[Big T]

Also, pouring solvent down the keyhole does not clean the contacts. Remove the switch and CAREFULLY open it up. Use a copper specific cleaner or very fine sandpaper to refresh the contacts, then rinse with contact cleaner, before reassembly

 

[Rich82GS750TZ]

Couldn't believe how cruddy it was in there. As stated, take your time. It's a spring-loaded trap, and a ball bearing that needs to go back in correctly to pop into the detents at each key position. I dismantled mine, slathered all the contacts w/ naval jelly, rinsed w/ water after 10 minutes. Made everything shiny and new looking, dried thoroughly w/ compressed air, cleaned w/ electrical contacts cleaner to evaporate any residual water. Then just a touch of deoxit to protect. FYI, it is possible to re-assemble the works exactly 180 degrees wrong. Best to make notes/take pics as you disassemble.

 

[pdqford]

Ditto!
And my GS750ET picked up over a volt at the coils after thus cleaning the ignition switch!

 

[robinelwood]

Hmm. Springs (4) and balls (2) are back in their holes, copper connectors cleaned and re-installed. Still nothing: Its cool to know what the key does (and why contact cleaner in the barrel didn't fix the electrics)...but the search continues.

 

[Brendan W]

Have you got a meter?
The red wire at the ign switch should have power permanently. When the switch is ON , power is fed back to the fuse box, orange wire, to the other three circuits.
Check for voltage at both sides of the main fuse, fourth from top. Check again at the red wire at the ign switch. Have a look at the wire bundle to the front of the bike at the steering stem. Over time wires break here due to repeated bending from steering inputs.
If power is present at the red ign switch and the contacts are clean, check that power is at the orange exit from the switch and check if it is arriving at the fusebox.

 

[robinelwood]

I have a meter, and have tested some of these things but not all of them. Thx

 

[Big T]

You should check the back of the fuse box.. Disconnect the red power wire from the battery, unbolt the fuse box and take the cover off. Also, the path you should follow is battery --main fuse- igni9tion switch- 3 fuses and each of those 3 circuits. You should have 12 V at every point

 

[salty_monk]

Maybe a break in the wire at the steering head…

if you can read the wiring diagram you can rule out the switch by shorting the contacts in the connector with a small length of wire….

 

[robinelwood]

As I always suspect: I was doing it wrong.

Multimeter showed everything good except the i​gnition switch/puck, even though all leads on the puck had continuity.

Further investigation showed that I had (as a previous poster warned) reassembled the internals 180 degrees wrong. I should have trusted my disassembly pictures. You'd think the narrow arm on the key barrel and the skinnier arm of the 'plus sign' in the electric switch would match up..b​ut no. the skinny arm goes in the fat slot. After reversing the internals, everything works beautifully. Thank you all for your assistance.​​

 

[robinelwood]

The narrower arm to the left would be a good fit for the key barrel...but actually, it goes in the wider one to the right. Go figure.​

 

[Rich82GS750TZ]

Yep, I made the same mistake. Fortunately, now that you know, you'll never do it again. Glad you got it sorted.