AgTalk Home
AgTalk Home
Search Forums | Classifieds (110) | Skins | Language
You are logged in as a guest. ( logon | register )

dashboard back light on a JD 7000's tractor
View previous thread :: View next thread
   Forums List -> Machinery TalkMessage format
 
slerjk
Posted 9/6/2017 22:48 (#6233554)
Subject: dashboard back light on a JD 7000's tractor


SW Ontario		My 20 yr old JD 7700 has the rectangular LCD portion of the dash's backlight either burnt out or a bad ground. The LCD portion is actually illuminated anytime the tractor is running, normally.
All the individual pto, transmisssion pres.,voltage, etc lights light up on start up. The FWD light does not light up during that test sequence. The 3 soft touch buttons on the left do not illuminate either. All the LCD gauges do work, but I can't see them at night. Any body know where to look first? The dash module plugs in with a 14 pin connector. Having trouble figuring which wire to trace for grounding, or how much more of the steering column do I have to dismantle.
Thanks
Top of the page Bottom of the page
BFarm
Posted 9/6/2017 23:25 (#6233587 - in reply to #6233554)
Subject: RE: dashboard back light on a JD 7000's tractor


WCIL		Just replaced a few bulbs on our 2000 7810 tractor. If you take the whole display out and turn it over, you can take some screws out and eventually get to the backside of the circuit board. There you will find lots of bulbs that twist 1/4 turn to remove. Not hard at all. All of them in there are the same part # for the warning lights, backlights, turn signals, etc. There was a # on our bulbs I believe was PC74 or something similar (not positive) which were less than a dollar each from RockAuto. Easy bulb to find at any auto place or online. JD part was R107890 and were $2.31 here. Should be a # on your bulbs you can google to be safe. Had 4 burned out, but good and bright now.

Edit to change part #

Edited by BFarm 9/6/2017 23:32
Top of the page Bottom of the page
johnypop
Posted 9/7/2017 06:21 (#6233723 - in reply to #6233554)
Subject: RE: dashboard back light on a JD 7000's tractor


ND		Replace the bulbs, very common.
Top of the page Bottom of the page
h1000
Posted 9/7/2017 10:19 (#6234135 - in reply to #6233554)
Subject: RE: dashboard back light on a JD 7000's tractor


NE		If I understand you correctly, the gauges work correctly and the LCD panel back light works properly with the lights turned off. The back light goes out completely when you turn on lights for evening operation. Please correct me if I am wrong.

The LCD gauge panel should be max brightness when the keys are on and the lights are off. When you turn on the lights, the dimmer control takes over and the LCD back light can now be dimmed.

What you indicate to me is that the dimmer could be set so low that panel won't light up when road or field lights are on. Set the dimmer to a higher setting. The other possibility is that something could be wrong with the dimmer control.

I'm having a similar problem in our 7800 right now but haven't taken the time to dive into the problem yet. I suspect my problem is burned out bulbs because the panel won't light during the day either.

I believe the bulb number is PC37 as I just replaced some of these in the corner post of our 8100.
Top of the page Bottom of the page
slerjk
Posted 9/7/2017 13:13 (#6234372 - in reply to #6234135)
Subject: RE: dashboard back light on a JD 7000's tractor


SW Ontario		Yes to be clear, all the LCD: Tach.,Fuel & Heat gauges work all the time. You need a flashlight to see them at night though. I tried a neighbour's '94 7800 out, & his LCD display lights up as soon as he turns key & starts it (with headlights off). Mine never lights up, no matter what.
As the Gents above said I will try the bulbs first. I did have the Module split in half to access the bulbs, but found them stubborn to remove, & didn't want to break anything else.

Thanks everyone for the direction. I tell you how much success I have.
Top of the page Bottom of the page
FarmerboyRoy
Posted 9/7/2017 10:56 (#6234199 - in reply to #6233554)
Subject: RE: dashboard back light on a JD 7000's tractor


NEWI		We have the same exact issue with our 7710. Was told by dealer whole display needed to be changed..... didnt wanna do that, so have been running it with no lights at night.

Hope you get it figured out!!

Gonna try and take apart and check the bulbs as BFarm said.
Thanks!!!
Top of the page Bottom of the page
BFarm
Posted 9/7/2017 13:14 (#6234376 - in reply to #6234199)
Subject: RE: dashboard back light on a JD 7000's tractor


WCIL		Nope, shouldn't have to replace display if it's the bulbs. Really easy to change. Four allen screws from the bottom near your knees, then the black trim comes off. Lift it at your knees, then pull towards you carefully as there are two hooks on the front. Then unbolt the display and unplug and start taking it apart from the back, 4 star headed screws. Nothing to it, and nothing will fall out. Bulbs twist in from the back side and make contact with circuit board (no wires). H1000 is correct on the dimmer adjustment with the headlights on. Had that happen once too. Push the center display button at the same time with either the top or bottom button to adjust. There is + and - printed near the buttons in regard to the dimmer.
Top of the page Bottom of the page
h1000
Posted 9/7/2017 13:46 (#6234413 - in reply to #6234376)
Subject: RE: dashboard back light on a JD 7000's tractor


NE		You wouldn't happen to remember how many bulbs I'll need to pickup before I start this by chance? Thanks!
Top of the page Bottom of the page
BFarm
Posted 9/7/2017 19:11 (#6234825 - in reply to #6234413)
Subject: RE: dashboard back light on a JD 7000's tractor


WCIL		I can't say for sure but think there is one for each warning light and turn signal, maybe one for the 3 buttons backlight. I had to replace four total and they were all for backlights only, so at least that many (I still had a couple working). Close to 20 in there altogether. Can buy pkg of ten from auto place. I tested continuity on the backlight ones since the others can be checked by turning the key, and only replaced the bad ones. The JD parts didn't show the bulb locations at least where I searched. And yes, our plastic is broke up too but still sits down where not noticeable.
Top of the page Bottom of the page
slerjk
Posted 9/7/2017 20:20 (#6234988 - in reply to #6234413)
Subject: RE: dashboard back light on a JD 7000's tractor


SW Ontario		According to JD online parts catalog there is i believe 27 total bulbs. eg. I looked at my backlight area for the LCD area & I think I saw 6 or 8 there.
Top of the page Bottom of the page
Two Hawk
Posted 9/7/2017 23:08 (#6235434 - in reply to #6234988)
Subject: RE: dashboard back light on a JD 7000's tractor


Southern Nevada desert		I think the 27 includes the warning lights and turn indicators, high beam, etc.
Top of the page Bottom of the page
slerjk
Posted 9/7/2017 17:15 (#6234682 - in reply to #6233554)
Subject: RE: dashboard back light on a JD 7000's tractor


SW Ontario		Finally a fix! Thanks BFarm & johnypop!
It was the bulbs. I had a couple spares from my 7320 side console. They fit in the socket but stand a bit taller at the base, They worked when I turned the key. I priced them at the local NAPA & they're 1.99 ea. & will pick up 10 in the morning. Also I needed to buy a T10 torx screw driver because 1 of the 4 screws was in a tunnel type recessed area that a "bit" type screw driver was too fat to fit in. Also some of the plastic dash pieces need attention as they are cracking apart where the screws hold the Module in place.
Gotta love Ag Talk!
Thanks again guys.
Top of the page Bottom of the page
Two Hawk
Posted 9/7/2017 17:32 (#6234703 - in reply to #6234682)
Subject: RE: dashboard back light on a JD 7000's tractor


Southern Nevada desert		$12.49 for 10 pc37 bulbs on Ebay
http://www.ebay.com/itm/Instrument-Panel-Light-Bulb-Wagner-Lighting...
Top of the page Bottom of the page
Jump to forum :
Search this forum
Printer friendly version
E-mail a link to this thread

(Delete cookies)