x500 hour mtr not working

[tractorhal]

serial # above A030000. Has combo fuel gage-hour meter. fuel gage works. Hour meter (.) will blink sometimes for 3-8 times, then stops. Have traced wires to connector and all have voltage, Blk. is ground, Wht.a ties into, changes to Blk. for grounding of the coils. Two yellows one for hour mtr., other for fuel gage. The Wht. comes from an interlock device, that basically provides spark. Have no way to test it. Everything else works. Tried a new hr. meter, same results.
Thoughts.

 

[Roadworthy]

You could try tracing the yellow wire for the hour meter to its source. Look for break points and poor connections. It could be loose on a connector somewhere, too. When the hourmeter blinks 3-8 times does it read out as the number of hours on the machine? Count the blinks - it may be a code explained in the manual indicating what's wrong.

 

[tractorhal]

I have traced the wire- (s) manually and checked with a continuity meter. I have power to the hour meter on the correct # wire. When I jumper the ground to bat. ground, and power to the correct yellow is when the meter shows hours and blinks-then stops. Remove power and connect it to the wht. mag terminal the meter works. It appears could be the interlock interface because the wht. comes from that, yet every thing that's tied to it works??

 

[jgayman]

There is a page in the technical manual that deals with testing the hour meter circuit. They have you measuring an AC voltage with the engine running. I've attach a photo of the page.

 

[tractorhal]

Thanks. Checked this morning. At the connector for meter 3.4-6 steady volts ac, sp4 is at x6 connector volts are 3.4-6, yet meter works for 5-8 blinks of (.) then stops. All had been working fine until pulled engine to change gasket between top and bottom of engine. My daughter was mowing 4-6 weeks ago and tractor quit once, not sure why. She is small, may have been seat safety, because farm land is uneven. Thanks again.

 

[tractorhal]

Tested the stator for correct AC voltage and is well in the specs. Rechecked splices and connections for correct voltage, same. Is there a test for the interlock module?
Thanks.

 

[jgayman]

Tested the stator for correct AC voltage and is well in the specs. Rechecked splices and connections for correct voltage, same. Is there a test for the interlock module?
Thanks.

Not that I can find. It's times like this where I really dislike the paper manual. The index/TOC is useless. I have the PDF version for my 2720 and you can easily search for topics. Example, the hour meter isn't even listed in the index but paging through the electrical section I found a section for it.

 

[tractorhal]

Thanks.
Just got back from Dover, will do some checking tomorrow. I have had difficulty finding parts on JD parts look up. There are times I have had to search another section within the same category to find part.

 

[jgayman]

Thanks.
Just got back from Dover, will do some checking tomorrow. I have had difficulty finding parts on JD parts look up. There are times I have had to search another section within the same category to find part.

I'm pretty good with parts lookup but the Technical Manual drives me crazy. I have a printed book and PDF for my 2720 but only the printed book for the X500. It is soooo much easier to find things on the PDF as you can search for words. So you can just key in "interlock module" and quickly look at every place it is mentioned. That has allowed me to find things that aren't listed in the Index/TOC. But on the printed book you are at the mercy of the Index/TOC. Like I said, I found the hour meter section by accident as it is not listed in the Index. One would think that under "Electrical" would be listings for "hour meter", "fuel gauge" and "ECU" (aka "interlock module") but that is not the case.

An interlock module is around $87 so it's not something you want to buy if you don't need to. Although the hour/fuel gauge is $107 so not exactly inexpensive in itself.

 

[tractorhal]

IT'S FIXED!
Bought manual. Did test, had power on yellow, said replace gage, no change, other than lost $'s. Did more testing, appeared to be interlock module from manual's limited diagnostic's of the interlock, new one installed, no change. The manual shows that the Blk. wire, changes to white, at a connector and once the key is in the on position, then started, the wire pick's up the impulse from the coils, through the interlock, to hour meter for recording, still no change. The engine seem to take longer to shut off than prior to the issues. Pulled shroud to check coils, if you grounded the coils the engine would not shut off, what was shutting the engine off was the fuel solenoid. The manual said when key is turned off the interlock was to ground the coils and close the fuel solenoid to stop engine, that didn't happen. Put two new coils on, and left new interlock module on, old hour meter and all was working correctly. I have no idea of what caused the coils to short out internally, other than the interlock module. I did not want to chance putting the old module on and loosing two coils.