Battery seems dead but third time's the charm

[bdimon]

I got a new battery and then a weird thing happened to my 2005 R1200RT.

I turn the ignition key on and there's a flicker of light on the dash before it goes dark. I push the starter button and get a weak "whuh-uh" before silence. Seems like the new battery is weak.

I turn the key on and off. Same thing. I repeat again but same.

The third or fourth time, the dash lights up brightly and the system goes through the self-check. When it's done, I push the button and the starter roars the engine to life. I ride off without any further issues.

I checked the battery terminal connections and they are tight. This has happened on several occasions.

The new battery is a Yuasa YTX20L-BS and the guy at the Not a BMW dealer said it was the correct battery.
https://www.yuasabatteries.com/battery/ytx20l-bs/

So I look it up and it is not what Yuasa recommends for the 2005 R1200RT. Yuasa recommends the YT19BL-BS. Here is how they compare:

Recommended What I Got
Model YT19BL-BS YTX20L-BS
CCA 170 270
Amps 1.8 1.8
Capacity 17.7 18
Acid Volume 0.95 0.93

From the numbers, I would say that the battery I got should be better than the recommended battery. Is there something other then these numbers that would make the battery I got wrong?

I put a tester gizmo on the battery and it measured 235 CCA and good voltage at the battery. After starting and revving the engine, the alternator test passed. I think it was 14.1 V.

Could this be some electrical glitch in the ignition switch and the timing is just a coincidence? What should I test next?

[JimVonBaden]

That is not the battery. It sounds like a bad ignition switch. Pretty easy to swap out.

Jim

[bdimon]

That is not the battery. It sounds like a bad ignition switch. Pretty easy to swap out.

Jim

I'm glad to hear it is easy. I hope it will not be too expensive. I guess it means a new ignition key and then re-keying the panniers and the trunk.

[bdimon]

More fun on the way home today. The speedometer, odometer, and cruise control did not work. After I pulled off the highway, I turned the key off, waited for the lights to go out, turned it back on, and waited for the self-test to finish before starting it up again. It all works again.

Hooked up the GS-911 and looked for the faults.

BMS-K
10220 CAN-bus Timeout: no communication with ABS control unit
The fault is not present now.
10444 Fuse activated for component Ignition Supply (starter relay, Immo (EWS) ring antenna, ignition coils, injectors)
The fault is not present now.
10218 CAN-bus Timeout: no communication with KOMBI (Instrument Cluster) control unit
The fault is not present now.
10219 CAN-bus Timeout: no communication with ZFE (Central Vehicle Electronics) control unit
The fault is not present now.

Integral ABS - CAN omitting the codes about the disconnected ABS
25153 Internal control module error - Communication timeout between main and control processors
The fault is not present now.
25156 CAN-bus timeout from KOMBI (coding data over CAN-bus)
The fault is not present now.

My best guess
The ignition switch is bad just as Jim surmised. That threw the "Fuse Activated" event and caused the other faults. Those faults shut down the speedometer and odometer.

[dcgsrider]

Yeah, mine had similar symptoms, but only at start up. Sometimes would have to cycle the key a dozen times before it would start.

Swapping out the switch was no big deal. Just a couple of torx screws to undo (nothing exotic like "security" head screws.) It's mounted at the bottom of ignition lock assembly and doesn't affect the keyed bits.

Part lists for $128.

Youtube: https://www.youtube.com/watch?v=aHhxrohxrt8

[JimVonBaden]

Yeah, mine had similar symptoms, but only at start up. Sometimes would have to cycle the key a dozen times before it would start.

Swapping out the switch was no big deal. Just a couple of torx screws to undo (nothing exotic like "security" head screws.) It's mounted at the bottom of ignition lock assembly and doesn't affect the keyed bits.

Part lists for $128.

Youtube: https://www.youtube.com/watch?v=aHhxrohxrt8

Paul is correct.

Jim

[bdimon]

That is not the battery. It sounds like a bad ignition switch. Pretty easy to swap out.

Jim

Jim, you were right. A new ignition switch solved the problem and it was easy to swap out.

[JimVonBaden]

That is not the battery. It sounds like a bad ignition switch. Pretty easy to swap out.

Jim

Jim, you were right. A new ignition switch solved the problem and it was easy to swap out.