glow plug curcuit M9000

[Orangepride]

I am having trouble finding the fault in my glow plug circuit for a M9000. I have a factory service manual that outlines the wiring and a few descriptions of the circuit but it is inaccurate for my specific tractor. All the diagrams and pictures show a different location for the glow relay as well as other relays too. The information there in the manual, as well as any I can find on the internet shows a four wire switch. Mine in the tractor is a five wire, and has as far as I can tell, an additional position for the ACC. I am afraid I have a freak setup, with newer components in an older frame. My main question is about how the GP circuit works. There is no light or GP indicator of any sort and I assume the circuit is controlled by a timer. There is a timer mentioned here in the forums and in my manual, but the schematics call it a key stop timer and do not indicate that it is tied to the function of the GP's. The key switch has a sticker around it that has a GP logo on it between the on and start positions, there is no detent here, just a long spring tension before the starter contacts. With the use of a multimeter I have confirmed that there is continuity on one wire of the switch when the key is held in the GP position I mentioned and also in the start position, but not in the on or acc positions. The glow relay has power and ground to all the proper contacts except for the one that activates it. Is this wire for the relay controlled by a timer or directly from the key switch as the book indicates? As I stated before, the repair manual I have appears initially to be incorrect on this, but everything I read elsewhere does not confirm nor deny.

 

[North Idaho Wolfman]

No timer on that model, just a relay and key switch.
There should be a hot signal (small wire) to the GP relay from the key switch (might be via a chip fuse), and a constant hot to the Relay (Big wire) (controlled by slow blow fuse), and ground and 2 outs one to an indicator (small wire) and one to the glow plugs large wire.
Glow plug relay

Slow blow fuses

 

[Orangepride]

Thanks for clarifying the inconsistency on the timer. I have power and ground on the large wires. Ground being continuity through the GP's. I have ground on one of the small signal wires. I will now check for a fuse in the signal wire from the switch. However, I still am not real clear on the proper operation of the glow plugs. When I want to start the tractor in the cold temps, do I have to hold the key in the glow plug position for a given amount of time before I engage the starter. How long would I hold it for a given temp.? and without the presence of an indicator, how do I know I even have the glow plugs enacted?

 

[North Idaho Wolfman]

I'm betting there is a bulb in the dash that is burned out that would indicate the glow plugs, but I could be wrong.

Turn the key to the GP position for about 5 to 10 seconds then straight on to start, You'll notice a difference right away if it's working right.

 

[Orangepride]

Final update... After an extensive search for a fuse or breaker turned up nothing I examined all the connectors under and around the column. All connectors were dusty, but tight. I blew them out and reconnected all back together. A multimeter test showed that everything was working so I reinstalled all components and gave it a try. I now hear the relay activate when I turn the key and the tractor starts fine after a ten second hold at the gp position. I find it odd that as modern the tractor is, it does not have an indicator for the GP circuit or a timer either. I am really glad to have the tractor running. Now I can keep the snow cleared without freezing my giblets off. Thanks all and have a great day...