Looking for some wiring diagrams for an MT345e

[GS650GL]

Even if you have 12.6 at the key switch you can still have low voltage at the fuses because some are powered by a relay, not directly from the key switch. I was only getting 7 volts on a couple fuses when I fixed mine and it was a bad relay. Then another time I had ground issues and added the extra ground wire. The firewall ground is on the right side about half way up the firewall and the wire goes to the clutch housing. I think I attached the extra ground wire at the clutch housing also.

 

[Earthur]

Even if you have 12.6 at the key switch you can still have low voltage at the fuses because some are powered by a relay, not directly from the key switch. I was only getting 7 volts on a couple fuses when I fixed mine and it was a bad relay. Then another time I had ground issues and added the extra ground wire. The firewall ground is on the right side about half way up the firewall and the wire goes to the clutch housing. I think I attached the extra ground wire at the clutch housing also.

Ok so i put this whole circuit on a sheet of paper so i could follow it in the Garage. When I checked the White wire with a red stripe at the key switch i had 12.54 volts, when i checked the top fuse in the box with the key on i only had 11.9 on all the fuses all the way down to the controller fuse. Then i went to the Pink wire at a15 for the gauge cluster and had 12.2.V, when i went to b11 on the gauge cluster i had 11.9. I am not good at electrical stuff so i dont know whats good or bad but it seems i should have 12.54 at the cluster on b11 which is fed from the fuse box right?

 

[Earthur]

How can i test the ground? or should i just run another one and see what happens?

 

[GS650GL]

There can be a slight voltage difference and 12.54 to 11.9 is such a small difference that it doesn't matter. Still pretty close to 12. And if you turn the key on and the glow plugs are on while you test, the voltage will definitely change. When I found my ground problem, I tested resistance with an ohm meter between the black ground wire in the harness under the dash and the negative battery cable clamp. I should have seen zero ohms or pretty close to zero which would indicate good continuity all the way through the harness back to chassis ground. I got about 14 ohms so I knew there was a bad ground splice somewhere in the harness. I had already verified all ground points were clean and tight. I cut some insulation off the harness ground wire under the dash and soldered in another wire and attached it to the ground point on the clutch housing which I already verified was good. Then I had zero ohms on the harness ground when I rechecked it. All the weird problems went away such as dash flickering, gauges not working right, starter clicking when pushing on brake pedals or turning on lights, flashers and work lights on one side dimmer than the other side, etc.

 

[Earthur]

I ran another ground wire to the display ground and it made no difference. Still no power to the display with the key on, and just everything flickers after i start the tractor. I am out of things to check at this point. I ordered another instrument display from Messicks. I read some where that the display has to be programmed, does anybody know how to do that?

 

[alexpops]

The dealer needs to do programming. You won't have the UPLOAD equipment or the files from LS. Before playing parts roulette, you want to rule out bad splices, cold solder joints, corrosion, mouse damage, etc. If you don't have the knowledge or equipment to check the electronics confidently, may be time to have a dealer tech look it over.

 

[Earthur]

The dealer needs to do programming. You won't have the UPLOAD equipment or the files from LS. Before playing parts roulette, you want to rule out bad splices, cold solder joints, corrosion, mouse damage, etc. If you don't have the knowledge or equipment to check the electronics confidently, may be time to have a dealer tech look it over.

Yeah I have ruled out all power and ground issues out at this point. I have around 12 volts on each power wire to the gauge cluster noted on the diagram above. Last ditch effort was a new ground wire to the gauge cluster from the clutch housing ground. Still no difference. There may be something else im missing the cluster
needs to operate but I can't find anything else it could be. Maybe some control or signal wire.. ? Idk

 

[GS650GL]

It is possible the instrument cluster itself is defective now that you have tested and verified other things. On your model tractor i don't think there is any programming that needs to be done with the dealer's service tool. There isn't a computer in the instrument cluster so it should be plug and play. The only things that would need to be programmed would be the ECU for the engine and the vehicle control module if they are ever replaced.

 

[Earthur]

**UPDATE***

Replacing the instrument cluster fixed all the issues. When I turn the key on now the cluster turns on and all the guages work before I even start the tracror. The hour meter did reset to zero however so I will have to see how to adjust that. Thanks to everyone for all the wiring help and the manual. That allowed me to rule everything out before shelling out the $395 for a new cluster.

 

[GS650GL]

Thank you for the update. Glad the problem is fixed. The only thing is, the hours displayed will not show the actual hours on the machine because a new cluster starts over again at zero. Unfortunately, there is no way to program the old hours into the new cluster. The only thing you can do is keep a record of how many hours were on it and the date when the cluster was replaced. Put a label on the dash somewhere with that information for easy reference.