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Need some technical assistance on my 03 RS.

Disconnected the battery to do the servo brake service. Reconnected it afterward, turned the key and only the oil pressure and battery lights come on, nothing else.

No power, temp gauge pins to the top. Removing the key it stays the same until pulling the negative cable off the battery.

Anyone run into this before?

Any ideas?

I replaced the battery today and it's doing the same as with the old battery.
 

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I don't have your bike, but I know my 2003 K12LT has a set of connectors on the positive pole. It could be that you didn't get all of those on your machine onto the post....
 

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The negative battery cable? On a K1200RS it is "The negative battery cables",there are TWO ground cables.
 

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I have just run into a similar problem. I have an '04 GT that I am doing some work on. I removed the battery for about a week, charged it and put it back in the bike. Now, as soon as I turn the key on, both fans run and the bike doesn't want to start. It takes about 15-20 attempts before the bike will start and stay running. It acts like the throttle positioner isn't working on start-up. I have done the ECU re-set procedure recommended in the Clymer manual at least a dozen times, took the bike out and rode it for about 10 miles and still no change. I'm pretty sure this is an ECU issue, but can't find any information on how to resolve the problem. Does anyone here have any ideas other than taking it to a BMW dealer ?

Ted
 

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I have just run into a similar problem. I have an '04 GT that I am doing some work on. I removed the battery for about a week, charged it and put it back in the bike. Now, as soon as I turn the key on, both fans run and the bike doesn't want to start. It takes about 15-20 attempts before the bike will start and stay running. It acts like the throttle positioner isn't working on start-up. I have done the ECU re-set procedure recommended in the Clymer manual at least a dozen times, took the bike out and rode it for about 10 miles and still no change. I'm pretty sure this is an ECU issue, but can't find any information on how to resolve the problem. Does anyone here have any ideas other than taking it to a BMW dealer ?

Ted
On all K1200 having "brick-engine" (K1200RS, K1200LT and K1200GT of 2003-2005),
both radiators fans will run continuous if the EFI system (ECU) sees a bad engine-coolant-sensor reading.
The fans are in fact ARE ALWAYS driven / started by ECU based on this sensor (even when all is OK)

In case of bad reading (or disconnected sensor), the system will:
a) assume the engine coolant temp to be CONSTANT 80 celcius (176 F - basically average operating temp). Of course this will cause issue with Cold-Start as the EFI controlled mixture (injection time) is all messed up by this assumption of engine being already warm.

b) as a "fail-safe" mode, in this condition, the ECU will run the fans continuous (until igntion is OFF)


You may have damaged the wire or disrupt this connector.
Check this Photo Album for location of connector and tests you can do (click on each photo for more text info):
https://get.google.com/albumarchive/101489741192933663432/album/AF1QipN3wKbI5mM6W9Kz8Z0LlnDS0czVu6FWt33uK0yb
 

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On all K1200 having "brick-engine" (K1200RS, K1200LT and K1200GT of 2003-2005),
both radiators fans will run continuous if the EFI system (ECU) sees a bad engine-coolant-sensor reading.
The fans are in fact ARE ALWAYS driven / started by ECU based on this sensor (even when all is OK)

In case of bad reading (or disconnected sensor), the system will:
a) assume the engine coolant temp to be CONSTANT 80 celcius (176 F - basically average operating temp). Of course this will cause issue with Cold-Start as the EFI controlled mixture (injection time) is all messed up by this assumption of engine being already warm.

b) as a "fail-safe" mode, in this condition, the ECU will run the fans continuous (until igntion is OFF)


You may have damaged the wire or disrupt this connector.
Check this Photo Album for location of connector and tests you can do (click on each photo for more text info):
https://get.google.com/albumarchive/101489741192933663432/album/AF1QipN3wKbI5mM6W9Kz8Z0LlnDS0czVu6FWt33uK0yb
Sailor,

Thanks for your reply. I will check to make sure I didn't inadvertently cause a problem with any of the connectors and perform the appropriate tests. I'll report back with results.

Ted
 

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Sailor,

I checked the connector for the head temperature sensor and it "appeared" to be o.k. I went ahead and disconnected it and tested it with my VOM (3.6K ohms @ approx. 50 deg. F). Re-connected the connector, turned the key on, hit the starter button and it started right up, idled normally and no fans running. Let it run for several minutes until fans cycled on and off. Everything seems to be back to normal. I can only assume that the connector wasn't fully seated or just making poor contact. At any rate, I owe you a beer ! If your travels ever take you to Sacramento, Ca., send me a PM and I will make good on that offer.

Ted
 

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Sailor,

I checked the connector for the head temperature sensor and it "appeared" to be o.k. I went ahead and disconnected it and tested it with my VOM (3.6K ohms @ approx. 50 deg. F). Re-connected the connector, turned the key on, hit the starter button and it started right up, idled normally and no fans running. Let it run for several minutes until fans cycled on and off. Everything seems to be back to normal. I can only assume that the connector wasn't fully seated or just making poor contact. At any rate, I owe you a beer ! If your travels ever take you to Sacramento, Ca., send me a PM and I will make good on that offer.

Ted
Glad it looks good now, but beep and eye (an ear) opened every time you turn ignition ON. On these models with Integral-ABS (version with servos) It is a good habit to wait 5 seconds before you hit the starter button as this leaved the ABS unit time to do its internal self check. Otherwise voltage goes down (when starter operates) and the ABS unit is still finishing internal diagnostic routine (takes about 4 to 5 sec.)

In my last 15 years doing maintenance on my K1200RS (an a few other for friends), I have seen a similar case (bad connection of this sensor) only ONCE.

My final "just-to-be-safe" solution was:
1) to double check tightness of the female metal connectors (inside the plastic connectors on harness side). Sometimes these can loose a bit of tension. A bit like if they had been forced opened just a tad too much from last connectors open/close.

2) I also cleaned the MALE side of the contact on the sensor side harness.


I have also seen a case where a large maintenance job (clutch, transmission removal) had been done just before the problem began to show up intermittently. Later, we eventually found out the job was done without disconnecting this sensor. In the process, the wire had been stretched / forced (wire is too short to allow needed movement of engine unless disconnected from under seat).
 

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Glad it looks good now, but beep and eye (an ear) opened every time you turn ignition ON. On these models with Integral-ABS (version with servos) It is a good habit to wait 5 seconds before you hit the starter button as this leaved the ABS unit time to do its internal self check. Otherwise voltage goes down (when starter operates) and the ABS unit is still finishing internal diagnostic routine (takes about 4 to 5 sec.)

In my last 15 years doing maintenance on my K1200RS (an a few other for friends), I have seen a similar case (bad connection of this sensor) only ONCE.

My final "just-to-be-safe" solution was:
1) to double check tightness of the female metal connectors (inside the plastic connectors on harness side). Sometimes these can loose a bit of tension. A bit like if they had been forced opened just a tad too much from last connectors open/close.

2) I also cleaned the MALE side of the contact on the sensor side harness.


I have also seen a case where a large maintenance job (clutch, transmission removal) had been done just before the problem began to show up intermittently. Later, we eventually found out the job was done without disconnecting this sensor. In the process, the wire had been stretched / forced (wire is too short to allow needed movement of engine unless disconnected from under seat).
Sailor,

I did check/clean the contacts in the connector and they look good, but the connector doesn't seem to have the same tension as most BMW connectors. I will figure out a way to make it reliable.

Concerning your comment about the start-up procedure, yes, I always wait for the system to finish it's electronic checks before hitting the starter.

This is my third K bike and I purchased this bike a few months ago as a project. The bike has very low miles and is in great condition, but I've always wanted to do a K project bike, so this one is being "customized". So, as I disassemble and remove unwanted components, I'm trying to keep testing for proper operation at each step to make sure I haven't created an ECU problem. I'm hoping not to run into problems, but if I do, I may be back to pick your brain again.

Thanks again for your help.

Ted
 

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Kudos to SAILOR and H96669 for their knowledge and willingness to help! I would likely have parted with my K1200 by now(14yrs old and 69K miles) were it not for knowing such help was available if needed.
 
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