Battery Tender Question

[TWILKIN650]

The last two times I hooked a Deltran Battery Tender Plus to the FJR through a Powerlet socket to charge after a few weeks of no riding, I can't get the flashing red light stop and stay solid red indicating that it is taking a charge. I've wiggled the Powerlet plug in the socket to no avail; flashing red light never goes to solid red.

So I break out the fancy schmancy BMW Advanced Battery Charging System charger intended for the new BMW true gel batteries (replaced one last year in my older R1100RS) using the same Powerlet plug, and the red flashing light stops instantly and completely charges the battery in several hours, finally going to solid green light.

So I say to myself, "bad Battery Tender Plus" but then try the Plus on a standard lead acid flooded battery in the old XS-2. Red light goes to solid instantly and charges the battery after a few hours. Just won't work on the FJR. What gives? What am I not understanding?

Will the BMW charger eventually cause harm to the FJR battery (which I gather from posts here is an AGM not a true gel battery)? I have pulled the BMW charger off the battery when it is charged in that case.

 

[Randy]

Battery Tender through Powerlet works for me. I dunno. Any chance the problem is in the pigtail that connects the Battery Tender to the Powerlet?

 

[TWILKIN650]

Battery Tender Plus pigtail > SAE connector > Powerlet plug > FJR = No solid red light.

Battery Tender Plus pigtail > SAE connector > SAE connector > XS-2 = Solid red light.

BMW Advanced Battery Charing System pigtail > SAE connector > Powerlet plug > FJR = Solid red light.

Based on the above, the Battery Tender provides current to the XS-2 battery but not the FJR, so I conclude that the pigtail coming out of the Plus is good. Is this logic correct?

 

[Toecutter]

I recently lost the power to my Escort through the Powerlet plug. I took it apart to find the connection was loose inside the plug. Check continuity to the battery and ground through the plug and receptacle.

 

[TWILKIN650]

toecutter, good advice and I will check as I've had them come undone too. But the exact same Powerlet plug works when its SAE connector is pulled off the Plus and installed on the pigtail of the BMW charger. Therefore, I've assumed the plug was O.K.

And the Plus does charge the XS-2 battery on a direct connection to the battery.

 

[apratt]

I had a problem like this also. Turned out I had two grounds on the bike. Exposed metal (e.g. bolt heads) at the front of the bike had zero ohms resistance to the negative battery terminal, but the back of the bike had 78 ohms consistently, at several points. Except the exhaust hanger bolts: they were also zero.

Run an ohmmeter from the ground side of the Powerlet directly to the negative battery terminal and see if it's zero or not. Mine was 78 ohms and the Battery Tender wouldn't work. After running a 12ga wire from the battery to the rear of the tank, everything's fine.

 

[Bounce]

Battery Tender through Powerlet works for me.

+1 (BT Plus and BT here and they both work)

 

[Feejer/Weejer man]

With all this talk I plugged mine in to the powerlet and it was full up in a few hours. I have an '03 bought end of July of '02. Ran the battery down once. Left the key on, bumb started it then drove it home and hooked it up to the B.T. Mine has set for quite a while waiting to take it in for the fix and in for 5 weeks while it was being fixed. Seems good to go.

 

[TWILKIN650]

apratt, I'll check it out! I have a second lead up front for heated grips that is tied to the negative battery terminal. Good call!