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1Back to top Go down   100rs fuel pump fuse Empty 100rs fuel pump fuse Sat Dec 26, 2015 10:01 pm

Flip2

Flip2
Silver member
Silver member
was hoping the other threads would get me through this issue but i need help please. 86 100 rs is blowing the fuel pump fuse when starter is pressed and there is no power at the fuel tank connector. the last time i rode the bike was immediately after i sprayed it down while cleaning and then rode up the rode to try to get any water to blow off and then left the bike sitting for several months, inside. I had sprayed deoxit on the most easily disassembled wire junctions under the fuel tank and else where prior. I'm a newbie to electrical troubleshooting/electrical systems but have a few days to try to figure this out hopefully.

1.Fuel pump fuse blows immediately after depressing starter. No volts measured at fuse (right side of fuse) until starter is pushed  , measures 11volts.

2. Ground above gear shifter cleaned/sprayed, looked fine. The other  frame ground under the tank looks fine no corrosion/sprayed. 
   
3. Ignition switch cleaned /sprayed,  tiny amount of buildup on contacts.

4. Fuel pump relay pins: 30# 12 volts measured Ignition On or Off.
                                  86# 12 volts Ignition On
                                  85# 10.5 volts Pressing starter- positive of  tester to positive battery, negative of tester to pin. Assuming this is measuring with the two pieces of the relay separated and the tester into socket? If not ,does the very top come off?                                 
                                         
5. Fuel pump runs if hooked to external power source.

6. No power at fuel tank connection, Ignition on, in green/ white wire or brown wire , white wire shows     10.5 volts, drops when starter is depressed. 

7. Battery charger will not read  fully charged under normal charging time , something draining battery?

    

2Back to top Go down   100rs fuel pump fuse Empty Re: 100rs fuel pump fuse Sat Dec 26, 2015 11:30 pm

Inge K.

Inge K.
VIP
VIP
Does the fuse blow when the tank connector is disconnected?

If not, you must search for a short to ground between the connector and the pump.

If, you must search for a short to ground between the connector and the fuse.
If, try also to disconnect the fan relay as this is protected by the same fuse
and the short could also be inside the fan relay.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

3Back to top Go down   100rs fuel pump fuse Empty Re: 100rs fuel pump fuse Sun Dec 27, 2015 2:21 pm

Flip2

Flip2
Silver member
Silver member
Inge thanks for the advice. Yes, no power when the connector is disconnected. I tried removing the other two relays, one at a time, and the fuse keeps blowing. 

Am assuming you are referring to removing the tape/wrap that covers the connector wires and visually inspect the wires going towards the fuse box?  

If so what kind of tape or wrap is recommended to wrap it back up? Seems like I could damage other wires/conncetions  at the same time but I'll do whatever I need to.

    

4Back to top Go down   100rs fuel pump fuse Empty Re: 100rs fuel pump fuse Sun Dec 27, 2015 3:27 pm

Inge K.

Inge K.
VIP
VIP
@Flip2 wrote:I tried removing the other two relays, one at a time, and the fuse keeps blowing. 

You must try to disconnect the rectangular one in middle on the right side in the relay box.

It normaly shouldn't be neceserry to undo any tape on the outside of the wires
as long as it looks OK and undamaged.....and not earlier been modified.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

5Back to top Go down   100rs fuel pump fuse Empty Re: 100rs fuel pump fuse Sun Dec 27, 2015 4:16 pm

Flip2

Flip2
Silver member
Silver member
ok thanks for pointing that out , i removed the fan relay and now i have power at the fuse connector and the fuse is not blowing, great! what should i do now?

    

6Back to top Go down   100rs fuel pump fuse Empty Re: 100rs fuel pump fuse Sun Dec 27, 2015 4:18 pm

Inge K.

Inge K.
VIP
VIP
Then you have a short to ground internal in the fan relay and need to find a new/used fan relay.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

7Back to top Go down   100rs fuel pump fuse Empty Re: 100rs fuel pump fuse Sun Dec 27, 2015 4:42 pm

Flip2

Flip2
Silver member
Silver member
that sounds easy enough. and could anything have caused the fan relay to go bad or do they just go bad with age?

    

8Back to top Go down   100rs fuel pump fuse Empty Re: 100rs fuel pump fuse Sun Dec 27, 2015 4:49 pm

Inge K.

Inge K.
VIP
VIP
Difficult to say what have caused the relay to short, it's not one of the common problems.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

9Back to top Go down   100rs fuel pump fuse Empty Re: 100rs fuel pump fuse Sun Dec 27, 2015 5:34 pm

Flip2

Flip2
Silver member
Silver member
wanted to add that i had forgot to reconnect the choke light switch when i was spraying deoxit everywhere and it was unplugged when this problem started, not sure if that could cause anything but thought you would want to know.

at $70 for a new temperature switch i would like to rule out anything contributing to the problem before a "new" switch goes bad. i saw some other posts pointing to checking the fan, etc ?

    

10Back to top Go down   100rs fuel pump fuse Empty Re: 100rs fuel pump fuse Sun Dec 27, 2015 6:59 pm

Inge K.

Inge K.
VIP
VIP
If the wiring for the choke light switch have been shorted to ground, your choke light would have been on all the time.
If the problem have been a shorted fan, fuse #7 would have blown instead of #6....this is a separate circuit inside the relay with its own contacts.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

11Back to top Go down   100rs fuel pump fuse Empty Re: 100rs fuel pump fuse Sun Dec 27, 2015 7:45 pm

Flip2

Flip2
Silver member
Silver member
darn!  i was hoping that could be a contributing factor to the faulty temperature  sensing switch, to be clearer than earlier ,  i left the choke connector(under the tank) unplugged and i'm assuming that means power was not able to reach the light  and or back from the light to complete the circuit , the choke light would not come on until i reconnected the connector yesterday .. sorry this is all a refresher and or new material to learn.

    

12Back to top Go down   100rs fuel pump fuse Empty Re: 100rs fuel pump fuse Mon Dec 28, 2015 2:39 am

Holister

Holister
Life time member
Life time member
Flip, the only thing the choke light has in common with the temp control unit (what you're calling the fan relay) is that the temp warning light and the choke light get their power from the same feed (thru fuse #1). They are switched to earth independently... so no concern.

Inge, please double check but I'm sure the fan is itself unfused. Being switched by the temp control unit it relies on fuse #6 thru the temp unit.
Fan problems are common enough so worth checking. Check for a short rather than applying 12v directly to the fan.
Cheers


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
  100rs fuel pump fuse Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

13Back to top Go down   100rs fuel pump fuse Empty Re: 100rs fuel pump fuse Mon Dec 28, 2015 6:29 am

Inge K.

Inge K.
VIP
VIP
Kaptain Holister wrote:Inge, please double check but I'm sure the fan is itself unfused. Being switched by the temp control unit it relies on fuse #6 thru the temp unit.

The PCB inside the fan relay is protected by fuse #6.
The fan is Powered via a separate set of contacts inside the fan relay
and protected by fuse #7.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

14Back to top Go down   100rs fuel pump fuse Empty Re: 100rs fuel pump fuse Mon Dec 28, 2015 7:10 am

Holister

Holister
Life time member
Life time member
Thanks Inge, I can see that now. The info in the fuse diagram at the top of the 'Troubleshooting' page needs to be updated. The wiring diagram shows 2 fuse inputs to the temp unit.
Cheers


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
  100rs fuel pump fuse Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

15Back to top Go down   100rs fuel pump fuse Empty update Sun May 01, 2016 4:13 pm

Flip2

Flip2
Silver member
Silver member
hi, just thought i would let you all know i finally replaced the the temperature sensing switch on this problem and that was enough to let the bike start, however i did not continue to test  for a short to ground going towards the radiator as someone suggested, i may get to to that point but now i have a new problem, thanks for the help on this one though

    

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