Instrument panel lights and gauges not working L3710

[tbryant]

The instrument panel Lights (glow plug, parking brake, all lights at the top of the panel) and the fuel and temp gauges are not working. The light that illuminates the panel does work. Is there a controller module that controls these functions? All the fuses ohm good on the fuse box at the firewall by the steering column. This started when I replaced the alternator. Any help would be appreciated.
tbryant

 

[85Hokie]

The instrument panel Lights (glow plug, parking brake, all lights at the top of the panel) and the fuel and temp gauges are not working. The light that illuminates the panel does work. Is there a controller module that controls these functions? All the fuses ohm good on the fuse box at the firewall by the steering column. This started when I replaced the alternator. Any help would be appreciated.
tbryant

My first thought is that you blew the large main fusible link - does the tractor start? But I think that would still control the dash lights.

Sounds like a wire feeding the panel is not hooked up or a bad ground. The new vs old alternator - exact same setup?

 

[tbryant]

My first thought is that you blew the large main fusible link - does the tractor start? But I think that would still control the dash lights.

Sounds like a wire feeding the panel is not hooked up or a bad ground. The new vs old alternator - exact same setup?

The main fuse 40 amp slow blow is good. The tractor starts and the lights, blinker, hazard, and instrument lights work. I have checked all the bulbs (battery, glow plug etc) they ohm good. there are 5 modules on the firewall and I can't tell if one is a control module for the gauges and other lights. The new alternator is the same setup as the old one. Thanks for your response.

 

[Dave_eng]

The instrument panel Lights (glow plug, parking brake, all lights at the top of the panel) and the fuel and temp gauges are not working. The light that illuminates the panel does work. Is there a controller module that controls these functions? All the fuses ohm good on the fuse box at the firewall by the steering column. This started when I replaced the alternator. Any help would be appreciated.
tbryant

What led you to change the alternator?

Having this NEW problem arise after changing the alternator makes me suspicious that the problem now was present leading to the alternator replacement.

Can you please measure battery voltage when the engine is running. One meter lead to + terminal and the other meter lead to the - terminal.

Dave

 

[GreensvilleJay]

'old skool' electrical had both gauges( temp and fuel) being fed from a common 'voltage regulated' source, at least in cars. This would give reliable readings even if battery wasn't a perfect 13.2
A good wiring diagram of your tractor would really help.

 

[tbryant]

What led you to change the alternator?

Having this NEW problem arise after changing the alternator makes me suspicious that the problem now was present leading to the alternator replacement.

Can you please measure battery voltage when the engine is running. One meter lead to + terminal and the other meter lead to the - terminal.

Dave

I changed the alternator because I didn't think it was working correctly. When I tested it running the voltage was less than when it was not running.

What led you to change the alternator?

Having this NEW problem arise after changing the alternator makes me suspicious that the problem now was present leading to the alternator replacement.

Can you please measure battery voltage when the engine is running. One meter lead to + terminal and the other meter lead to the - terminal.

Dave

the readings. Battery engine. Off. 12.7; engine on 12.6; engine on at 2000
Rpms. 12.7; lights. On 2000 rpm 12.4
Have changed the alternator twice. First time battery was running down replaced the battery and had the alternator rebuilt. Never got a reading of 13 which seemed to be a reasonable reading. Replaced the alternator with a new one. During install I blew the slow blow 40amp fuse. Replaced and started tractor after I shutdown and restart Had the instrument panel problem. Switched the alternator and still have the problem. I am getting fast at installing alternators. Help please

 

[85Hokie]

speaking of voltage regulator....... could that be the problem? Have you looked into that?

 

[GeoHorn]

If you didn’t work on the instrument panel when you changed-out the alternator then that’s unlikely to be the problem. The most common cause of panel failures are loss of ground.

 

[tbryant]

speaking of voltage regulator....... could that be the problem? Have you looked into that?

I did an ohm test from the post with the nut hot wire to the plugs horizonal post and ohmed ok . Don't know what that means.

 

[wgator]

tbryant, go to the following links below and download the workshop manual (2 parts WSM) for your tractor. According to wsm your voltage regulator is part of alternator. In part 2 of wsm, on pdf page 97 (wsm page 9-S17), perform those tests on you alternator. Those indicators you say are not working get voltage from the regulator. If you don't have battery voltage at alternator wire harness connector B1 (not alternator terminal B1) per the test, the only place it can be losing it is between the 40 amp slow blow fuse and that wire connector (by schematic). If no battery voltage at connector on B1, no charge of battery.

WSM PT 1 CLICK HERE
WSM PT 2 CLICK HERE

 

[85Hokie]

I did an ohm test from the post with the nut hot wire to the plugs horizonal post and ohmed ok . Don't know what that means.

I would do a voltage test on the output leads..... engine will need to be running.

EDIT gator beat me to it ..... and better instructions too!

 

[tbryant]

My first thought is that you blew the large main fusible link - does the tractor start? But I think that would still control the dash lights.

Sounds like a wire feeding the panel is not hooked up or a bad ground. The new vs old alternator - exact same setup?

It was a plug problem. unplugged all conntections and sprayed with contact cleaner and it works now. Thanks for you help.

 

[85Hokie]

It was a plug problem. unplugged all conntections and sprayed with contact cleaner and it works now. Thanks for you help.

you gotta love the easy fix!!!! I wish all problems were as easy to fix!

 

[tbryant]

tbryant, go to the following links below and download the workshop manual (2 parts WSM) for your tractor. According to wsm your voltage regulator is part of alternator. In part 2 of wsm, on pdf page 97 (wsm page 9-S17), perform those tests on you alternator. Those indicators you say are not working get voltage from the regulator. If you don't have battery voltage at alternator wire harness connector B1 (not alternator terminal B1) per the test, the only place it can be losing it is between the 40 amp slow blow fuse and that wire connector (by schematic). If no battery voltage at connector on B1, no charge of battery.

WSM PT 1 CLICK HERE
WSM PT 2 CLICK HERE

Thanks for he information. I have solved the insturment problem it was a dirty plug. unplugged all plugs and sprayed with contact cleaner and it works now. Thanks for the copy of the manual and help.

 

[wgator]

Good job and great news you got it fixed.

 

[iwlf]

I have the same issue. What plugs did you find to check other than the one on the back of the instrument cluster?

Thanks