L-3400 Will only idle.

[longhairlimy]

I would like to know what computer is going into limp mode? The intellipanel on the Grand L 30 series has no control of the engine other then the kill/run solenoid.

David Kb7uns

I was kind of not following that line either. Texasjohn, Tell me more!

 

[texasjohn]

I discussed my problem and fix some time ago in this thread:

http://www.tractorbynet.com/forums/...01216-grand-l5030-starts-idles-perfectly.html

I invite all to read that thread in detail rather than me repeat it all here. Focus on my posts...all others are the usual suggestions.

The net is that a bad/loose connection at the solenoid/travel speed sensor WILL allow perfect starting, all RPM's desired while stopped, AND extremely slow forward HST travel BUT engine dies immediately under any load.

I attribute this to the intellipanel "fail safe " function...see page 9-M14 of the L5030 WSM..."it is a function that the entire system operates safely when a part of the system gets in trouble"

I can reliably recreate the behaviour by disconnecting/connecting the sensor cable.

I was kind of not following that line either. Texasjohn, Tell me more!

 

[Coyote machine]

In ten words or less I think what TJ is trying to convey is the onboard computer puts the tractor into 'limp home mode' for a lot of minor issues that don't have to render it dead. It protects the tractor from possible damage from more serious events, like no oil or overheat condition.

 

[longhairlimy]

I discussed my problem and fix some time ago in this thread:

http://www.tractorbynet.com/forums/...01216-grand-l5030-starts-idles-perfectly.html

I invite all to read that thread in detail rather than me repeat it all here. Focus on my posts...all others are the usual suggestions.

The net is that a bad/loose connection at the solenoid/travel speed sensor WILL allow perfect starting, all RPM's desired while stopped, AND extremely slow forward HST travel BUT engine dies immediately under any load.

I attribute this to the intellipanel "fail safe " function...see page 9-M14 of the L5030 WSM..."it is a function that the entire system operates safely when a part of the system gets in trouble"

I can reliably recreate the behaviour by disconnecting/connecting the sensor cable.

Thank You,As i know understand how i need to buy a shop Manuel for my Tractor. Good reading.

 

[texasjohn]

Exactly...and the various conditions that cause the "limp" mode are poorly or not at all described in the WSM. However, the decisions are based on apparent input from various sensors. If a connection is bad, sensor input is erroneous. There is an actual computer network in the tractor that reads the sensors digitally and a computer which applies software rules and outputs info via error codes and info to the intellipanel display. It will also actuate the key stop solenoid on occasion. Quite clever, actually.

In ten words or less I think what TJ is trying to convey is the onboard computer puts the tractor into 'limp home mode' for a lot of minor issues that don't have to render it dead. It protects the tractor from possible damage from more serious events, like no oil or overheat condition.

 

[longhairlimy]

Anymore sensor needs to be in everyone's mind when attempting to work on anything.One needs to by 1/2 mechanic,1/2 electrician.

 

[Coyote machine]

Anymore sensor needs to be in everyone's mind when attempting to work on anything.One needs to by 1/2 mechanic,1/2 electrician.

This type of computer override/lockout is built into many engines, and has been for a long time. My old year 2k Mercury outboard has a similar computer controller that will render the engine useless under many conditions, and only allow a low speed limp home, 7 MPH max until codes are cleared in the ECU. Newer CPU's in today's tractors essentially do the same thing but are way less complex in their diagnostics and repairs than $25K+ boat engines.
On your tractor, the solution is easy, find and repair/replace the faulty sensor, back to work.

 

[papapaul]

I'd be sure to put a new fuel filter on before I did anything expensive. The 3 cylinder diesel on my Mahindra acts just like that when the fuel filter goes bad. Oops, I see you said you put a new filter ion it. Last week I put a new filter on mine and the filter was such a close fit that it wouldn't let fuel past the top. I had to file a notch in the upper housing to get the fuel top flow. It is hard to find these filters and I had brought the old one into the parts store and we sized it by eye.

 

[longhairlimy]

I'd be sure to put a new fuel filter on before I did anything expensive. The 3 cylinder diesel on my Mahindra acts just like that when the fuel filter goes bad. Oops, I see you said you put a new filter ion it. Last week I put a new filter on mine and the filter was such a close fit that it wouldn't let fuel past the top. I had to file a notch in the upper housing to get the fuel top flow. It is hard to find these filters and I had brought the old one into the parts store and we sized it by eye.

Good Call papapaul. As this and fuel should always be first on one's list. I have ran into bad fuel. Thanks for you comment..