Electrical Problems

[Texasmark]

Hello again.

Working on the display for the 895, with a 1991 build date best I can tell....run was from 1990 thru 1994. Just received the two notebooks, Volume 1 and 2 of the Service Manual for that tractor, OEM issue reprints, really professional prints with heavy duty 3 ring notebooks for containment. As I mentioned earler, I also have that size of service manuals for the 395. I'm working on power to the display trying to get the tach and coolant displays to work. The warning lights for brake, oil pressure, and alternator are working fine but the center, removable display containing the coolant temp and tach are still inop, totally dead.

Being totally dead I figured that there is a power supply problem. Went to the electrical sections for the XL cab and in both manuals there is a wiring diagram showing 3 rows of fuses for that XL cab just inboard of the windshield, and behind the display. On mine, the center row is missing. Also the location of the 5 Amp fuse that is supposed to power that part of the display is not in the Positon 2 fuse slot as both manuals show.....they are identical in every respect for the XL cab. I checked all the fuses and checked the 12v buss feeding both rows of fuses and it was good to every fuse.

The connector to the panel is probably 30 pin and 2" in diameter, the only connection of any kind to the panel. Apparently the tach is electronically driven. Probably 20 wires in the connector and 10 slots with no pins. The manual shows 3 connectors for connecting to the panel and they are nothing like the one on the rear of the panel.

Question is you folks that know these tractors, do you have any ideas whereby I can find out what pins get power and ground so that I can see if power is missing and causing the problem.
Thanks for your time.

 

[BarnyardEngineering]

I'm thinking that information would be in the Service Manual, which is what you have.

 

[Janicholson]

Hello again.

Working on the display for the 895, with a 1991 build date best I can tell....run was from 1990 thru 1994. Just received the two notebooks, Volume 1 and 2 of the Service Manual for that tractor, OEM issue reprints, really professional prints with heavy duty 3 ring notebooks for containment. As I mentioned earler, I also have that size of service manuals for the 395. I'm working on power to the display trying to get the tach and coolant displays to work. The warning lights for brake, oil pressure, and alternator are working fine but the center, removable display containing the coolant temp and tach are still inop, totally dead.

Being totally dead I figured that there is a power supply problem. Went to the electrical sections for the XL cab and in both manuals there is a wiring diagram showing 3 rows of fuses for that XL cab just inboard of the windshield, and behind the display. On mine, the center row is missing. Also the location of the 5 Amp fuse that is supposed to power that part of the display is not in the Positon 2 fuse slot as both manuals show.....they are identical in every respect for the XL cab. I checked all the fuses and checked the 12v buss feeding both rows of fuses and it was good to every fuse.

The connector to the panel is probably 30 pin and 2" in diameter, the only connection of any kind to the panel. Apparently the tach is electronically driven. Probably 20 wires in the connector and 10 slots with no pins. The manual shows 3 connectors for connecting to the panel and they are nothing like the one on the rear of the panel.

Question is you folks that know these tractors, do you have any ideas whereby I can find out what pins get power and ground so that I can see if power is missing and causing the problem.
Thanks for your time.

One thing not mentioned is a ground fault. If the electronic displays are grounded separately from the lights that could be it. Using a test light can assist the diagrams in tracing power, or ground fault. Jim

 

[used red MN]

Hello again.

Working on the display for the 895, with a 1991 build date best I can tell....run was from 1990 thru 1994. Just received the two notebooks, Volume 1 and 2 of the Service Manual for that tractor, OEM issue reprints, really professional prints with heavy duty 3 ring notebooks for containment. As I mentioned earler, I also have that size of service manuals for the 395. I'm working on power to the display trying to get the tach and coolant displays to work. The warning lights for brake, oil pressure, and alternator are working fine but the center, removable display containing the coolant temp and tach are still inop, totally dead.

Being totally dead I figured that there is a power supply problem. Went to the electrical sections for the XL cab and in both manuals there is a wiring diagram showing 3 rows of fuses for that XL cab just inboard of the windshield, and behind the display. On mine, the center row is missing. Also the location of the 5 Amp fuse that is supposed to power that part of the display is not in the Positon 2 fuse slot as both manuals show.....they are identical in every respect for the XL cab. I checked all the fuses and checked the 12v buss feeding both rows of fuses and it was good to every fuse.

The connector to the panel is probably 30 pin and 2" in diameter, the only connection of any kind to the panel. Apparently the tach is electronically driven. Probably 20 wires in the connector and 10 slots with no pins. The manual shows 3 connectors for connecting to the panel and they are nothing like the one on the rear of the panel.

Question is you folks that know these tractors, do you have any ideas whereby I can find out what pins get power and ground so that I can see if power is missing and causing the problem.
Thanks for your time.

The wiring diagram does not show where the wires go in the machine harness? Finding the destinations of their opposite ends in the schematic should give you that information. Before you spend a lot of time on it I would contact Ag Express
The page that link opens to says manufacture of wiring harnesses. Believe me when I say they also offer a repair service of all brands of instrument displays for tractors, combines almost ANY agricultural or industrial related electronics that have displays. Scroll to the bottom there is phone numbers to call. Ask them if what you’re experiencing is a common problem. Ask them what you should check before sending the instrument cluster to them for repair.

 

[Texasmark]

One thing not mentioned is a ground fault. If the electronic displays are grounded separately from the lights that could be it. Using a test light can assist the diagrams in tracing power, or ground fault. Jim

Jim, the problem is that I have this multi- pin connector, pins all the same gauge and don't know which wires bring in voltage and ground. I guess if the designer was conventional in their wiring color code, voltage would be red and ground black. In thinking about what you said, I'll be out there today and check the wiring harness at the connector and see if the designer was conventional or not. Thanks

 

[Texasmark]

The wiring diagram does not show where the wires go in the machine harness? Finding the destinations of their opposite ends in the schematic should give you that information. Before you spend a lot of time on it I would contact Ag Express
The page that link opens to says manufacture of wiring harnesses. Believe me when I say they also offer a repair service of all brands of instrument displays for tractors, combines almost ANY agricultural or industrial related electronics that have displays. Scroll to the bottom there is phone numbers to call. Ask them if what you’re experiencing is a common problem. Ask them what you should check before sending the instrument cluster to them for repair.

Currently the hood and grille are on and I work alone. The stack is vertical and well rusted into one unit so removing it would probably mean tearing up the mating surfaces requiring replacement.....so for now that's out.
I've been toying with the idea that I could rig up some ropes from the top of the shed and install hardware on both ends of the hood and with a couple of ropes, just work the hood up and out of the way over the engine....I guess that's what I have been putting off but it looks like time to act if I expect to get anywhere. Thanks and thanks for the tip on possible help. Since this brand is a popular tractor....basic design built for many years and mine from '90 pr '91 thru '94, might be that the volume was enough to get some attention at their business.