BMW K bikes (Bricks)

You are not connected. Please login or register

View previous topic View next topic Go down  Message [Page 1 of 1]


1Back to top Go down    No electrical power on '85 K100 Empty No electrical power on '85 K100 on Mon May 06, 2019 1:04 pm

Moore152

Moore152
active member
active member
Hello everyone

I have an '85 K100 showing no electric power in any system. No power to dash, lights, starter, anything, no relay clicks, like there's no battery or circuit at all. 
One year ago the bike was parked in my garage with fuel issues, but with good electrical power and would turn the starter just fine.
I swapped fuel injectors today and now no electric power in any system. No power to dash, lights, starter, anything, no relay clicks, regardless of key on or off, like there's no battery or circuit at all. 

when I removed the fuel tank to inspect the wiring, I found lots of evidence of new mouse/rat nesting..but no chewed wires yet

-fuses are good
-Swapped "OK " battery with brand new battery and tested good with multimeter  
-triple checked connections on battery and under tank, everything is tight
-checked dash wiring connection, removed and reconnected (the dash is in rough shape but powered on in the same spot a year ago..)
-checked grounds. Is there supposed to be a ground wire around the rear brake pedal?
-Bypassed ignition (key) switch a long time ago, I twisty tie red and green when i want to start it
-HALL and injectors swapped, unrelated

The headlights and brake lights are all currently disconnected, just as they were when I had good power a year ago 

I had to run this $800 K100 hard through the troubleshooting flowchart when I first bought it so I have a decent grasp on the systems.  Replaced the fuel pump, fuel/ignition relay, had to unstick the injectors, but I got it on the road.  

Unfortunately that flowchart starts with good power/circuit. The bike is completely dark and I have no idea where to start here.

    

2Back to top Go down    No electrical power on '85 K100 Empty Re: No electrical power on '85 K100 on Mon May 06, 2019 1:47 pm

mike d

avatar
Life time member
Life time member
If you look in the Portal page, in the electrical section, there is a link called electrical diagrams. Opening that will reveal an interactive diagram set, where you can select individual circuits. I would start there and follow the live and earth runs with a multimeter.

Mike

    

3Back to top Go down    No electrical power on '85 K100 Empty Re: No electrical power on '85 K100 on Mon May 06, 2019 4:00 pm

duck

duck
Life time member
Life time member
Does the clock in the cluster work?

Is the ground cable attached to the left side of the transmission near the shift lever?


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S (K1 front end)
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

4Back to top Go down    No electrical power on '85 K100 Empty Re: No electrical power on '85 K100 on Mon May 06, 2019 5:52 pm

Laitch

Laitch
Life time member
Life time member
@Moore152 wrote:No power to dash, lights, starter, anything, no relay clicks, regardless of key on or off, like there's no battery or circuit at all. 

-triple checked connections on battery and under tank, everything is tight

-Bypassed ignition (key) switch a long time ago, I twisty tie red and green when i want to start it
Check under the seat. The electronic fuel injection control plug might have backed out enough to lose contact. If so, clean it with DeoxIt, plug it in tightly and be certain its latch is holding it in position. Check the condition of the wires at the tight bend  that emerges from that plug.

Other than that, try using a better quality twisty tie, or induce lightning to strike it.



Last edited by Laitch on Mon May 06, 2019 8:19 pm; edited 1 time in total


__________________________________________________
1995 K75T 73,000 miles
 No electrical power on '85 K100 Usa-lo10
    

5Back to top Go down    No electrical power on '85 K100 Empty Re: No electrical power on '85 K100 on Mon May 06, 2019 6:09 pm

Point-Seven-five

Point-Seven-five
Life time member
Life time member
First thing is to see if your meter shows 12.8 volts between the + terminal on the battery and the ground point above the shift lever.  If there is, connect the negative terminal of the meter to that ground connection.

Then start at the battery + terminal and check for 12v at each point where the power is transmitted through the bike.  With the ignition turned on pretty much any red wire will have 12v on it.

Next thing is to check all the terminals on the fuse block.  Pull the fuses out and stick your meter probe into the socket.  A bunch of them get power from the battery.  I suspect that is where you will find the best clues to your problem.


__________________________________________________
Present:
1994 K75RT
1991 K100RS

Past:
1994 BMW K75S
1992 BMW K100RS
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

6Back to top Go down    No electrical power on '85 K100 Empty Re: No electrical power on '85 K100 on Thu May 09, 2019 7:27 pm

Moore152

Moore152
active member
active member
@duck wrote:Does the clock in the cluster work?

Is the ground cable attached to the left side of the transmission near the shift lever?
I came back the next morning and saw this shifter ground wire disconnected and sitting under the battery tray.... I was almost too embarrassed to followup. Power is on, thanks guys.

onto the next issue but I'll keep the same thread.

It took 20 seconds of cranking to fire. Runs smooth for a few seconds, then roughens up, then starts audibly/visibly knocking unless I hold that starter button to add fuel. Dies immediately on throttle, unless i warm it up like this for a minute at idle w/ the starter button, then I can barely surge to 4krpm but usually dies. No oil smoke. It's running lean it appears and I want to limit testing until I think I have a solution.

It's starting up quick now...but it randomly failed to start yesterday, so I am immediately suspecting the 35 y/o jetronic "computer" or its sensors. I press that stupid "ecu" connector in every time I try to crank it, even if it looks good.

OEM fuel pump and injectors were replaced 1yr ago as they were seized
This is a new but very cheap domestic fuel pump for Fords....it could be bunk...but it ran the bike 2 years ago
I need a fuel pressure tester, but the fast starts and random no start, plus stories here, are leading me towards jetronic...wisdom will be much appreciated.

    

7Back to top Go down    No electrical power on '85 K100 Empty Re: No electrical power on '85 K100 on Thu May 09, 2019 7:37 pm

92KK 84WW Olaf

92KK 84WW Olaf
Life time member
Life time member
Holding the starter like that points to the FICU under the sat...or more likely the plug connector to it is disturbed, not plugged in properly or pins need cleaning.....


__________________________________________________
1992 K100LT 0193214 Bertha Alaska Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 58,645 now 96,650 miles
1983 K100RS 0011175 Fricka 29,495 miles Damn K Pox Its a Bat outta Hell
    

8Back to top Go down    No electrical power on '85 K100 Empty Re: No electrical power on '85 K100 on Fri May 10, 2019 1:08 am

duck

duck
Life time member
Life time member
Meh, we're all human and do stupid stuff.

I once spent an hour and a half tearing a K75 apart trying to figure out why in the hell it wouldn't start only to remove the gas cap and discover that the tank was empty.

And then there was the time I changed the oil on my K1100RS.  Once I'd refilled it and was finishing up I saw the new oil filter that I hadn't bothered to install was sitting on the ground by the front wheel.


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S (K1 front end)
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

9Back to top Go down    No electrical power on '85 K100 Empty Re: No electrical power on '85 K100 on Sun May 12, 2019 7:07 am

Stumpy

Stumpy
Silver member
Silver member
I had problems with my K100. I bought an Autel PowerScan PS100, it can test individual circuits as it is powered from the battery. It can check fuses and it can be reset if the circuit blows.
I thought it was expensive until I started using it, I found a broken wire hidden inside the loom.

    

View previous topic View next topic Back to top  Message [Page 1 of 1]

Permissions in this forum:
You cannot reply to topics in this forum