PARTIAL display fault

[PeterL]

A bit of background- I've been riding and wrenching since the mid 60's. Retired engineer. W-A-Y too parsimonious (ie: cheap) to pay someone for what I can do myself.


I've owned my 2005 RT for about 6 months now, 32k on the clocks. Aside from the cruise control being balky, which a shot of contact cleaner into the bar switch every month or so seems to handle, I've really enjoyed the bike. (disclaimer- I've ridden many friends BMW's, but this is the first I've owned/worked on)


A few weeks back, I got a DWA error on the dash. Looked it up, found and fixed. Now, however, when I turn the ignition on, both the fuel and temp readouts are completely blank. Everything else seems to be fine. I've disconnected and reconnected the main battery, no change. I've Googled until my fingers bled (and once upon a time I used to *write* search engines!) but haven't come up with any viable possibilities. If anyone out there has any suggestions I'd be deliriously happy to hear them. Otherwise I'll reluctantly give my local shop a big chunk of this months SSDI check. Waahhh!


Thanks all,


Peter

[David.]

When I turn the ignition on, both the fuel and temp readouts are completely blank.

Are the readouts blank when the engine is running.

On my 2012 Camhead, with the ignition on, if the Emergency off switch (kill switch) is in the "stop" position, the fuel gauge does not display. When the kill switch is in the "run" position, (engine not started),  the fuel gauge shows. The same applies to the engine temperature gauge.


(Not a Camhead but the kill switch is the same).

This may not be applicable to a 2005 Hexhead but just a thought. I remember that the kill switch is different on a Hexhead but does have two "off" and a "run" position.

[PeterL]

No, I start the engine, but those two bar displays remain totally blank (no segments showing).


Thanks,


Peter

[rangemaster728]

Ok...some random thoughts...

1. If the LAST thing you did prior to this error was work on the DWA try disconnecting the alarm unit from Canbus... it might be loading the network and you’re not getting temperature and fuel information. And another thing came came to mind....look at the DWA connector pins, especially the one connecting to Canbus and the instrument unit:

Also look at any wiring harnesses you might’ve moved when previously troubleshooting to make sure nothing is pinched or cut.
If you can’t find anything definitive there by removing the connector keep in mind that when a bike doesn’t have a DWA unit a 120-ohm resistor plug is installed in place of the unit as a network terminator.

2. As you likely know, you really won’t get any temperature information until the engine warms up. Have you let the bike sit and idle for a while so the temperature actually comes up? It could be when you start the bike you just have a cold engine, hence no temperature display, and you have had a fuel strip failure which would explain the fuel level being zero.

3. IF you have a GS911 diagnostics unit I seem to remember you can test the individual gauges and indicators... try that, or maybe find somebody local with a GS911 that can assist you.

4. Again, with a GS911 you may be able to interrogate the bike and find out if fuel level and temp data is actually present on the bike network. that being said, both of those sensors failing at the same time is highly unlikely.

5. The fuel level sensor send data to the central electronics unit; the oil temperature sensor sends data to the engine control unit...two different modules. The fact that both values aren’t making it to the KOMBI (display) module may indicate something has gone awry with your instrument cluster. Have you checked the plug on the back of the KOMBI module for clean pins, corrosion, etc? I believe pins 1 & 2 are the Canbus connection.

I’ll be watching this thread with interest.

Sent from my iPad using Tapatalk

[rangemaster728]

Peter:

Message sent...you can call me if you like...


Sent from my iPad using Tapatalk

[rangemaster728]

Just updated my reply above with more possible items...


Sent from my iPad using Tapatalk

[PeterL]

Thanks for the thoughts...


I understand the temp not reading until things warm up, but the fuel gauge went out as well. Other than those two items everything else displays/works properly.




I opened the alarm box courtesy of a right-angle driver, as I just didn't feel like spending a week removing/replacing the entire tail section plastics as BMW specifies. No wires shifted nor pinched. I have not disconnected the CANBUS connector, as I do not have the proper resistor on hand and it's a 3+ hour round trip to get one. I will try at least unplugging and reconnecting.


No other changes had been made, so I was/am at a loss to understand this particular failure. I'm keeping at it, but if I can't resolve in another week or two I guess I'll just give it to the shop. I've got two other 'project' bikes in my garage at the moment, not looking to add this to the pile. Now that our snow has melted, it's actually a quite a nice riding day. Guess I'll go put a few on the Yamaha in consolation. (Why is it I finally acquire a 'stable', but only when I'm too old to ride as often/far as I still want to? Not hardly fair IMHO!)


Regards,


Peter

[rangemaster728]

Peter:

OK...the assumption here is you were working on the DWA because had a bad alarm unit battery, right?

If that’s the case, did the fuel/temp indicator problems start immediately after you changed the DWA battery?

Gregg


Sent from my iPhone using Tapatalk

[PeterL]

They occurred simultaneously. The DWA warning appeared and the two bar graphs had failed when I went to ride one morning. I attacked the DWA battery issue first as it was the one item I found information on online, and I wanted to eliminate the faint possibility that one could have impacted the other. As rangemaster728 detailed, the two readouts share no obvious commonalities other than the display unit itself. But it strains credulity to think that the display would operate properly in all other areas save these two readouts. As Groot might say- I_am_stumped.

[rangemaster728]

OK...your RT is a 2005; how old is the bike battery? Low battery voltage/capacity can cause a variety of gremlins...


Sent from my iPhone using Tapatalk

[David.]

Found this thread on BMWSportTouring, Instrument cluster problems 1200rt, https://www.bmwsporttouring.com/topic/6 ... ms-1200rt/

The problems highlighted are more than fuel and temp. readouts being blank but makes interesting reading.

"My dealer checked it out, claimed it had the wrong plugs (they were the original plugs, came in the bike new!) So they replace the plugs and the instrument display worked OK. Now here is the interesting part. Several months later I was working on the bike and fiddled with the plug wire covers on the heads. After that the display problem came back, so I went back and made sure the plug wire, coil connections were good and tight and it fixed the display problem. The bike now has 29k miles and the display still works fine. Absolutely a true story."

"The bike is fixed, I have to give Max BMW all the credit they did a great job determining what the issue was without replacing unnecessary parts. True mechanics. They found a number of additional wire ties installed by the previous owner that was causing stress on the harness. To the point that it was cutting into the harness."