Tachometer

   / Tachometer #1  

BigTex

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Jun 16, 2003
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4
My Tach has stopped working. How do you go about checking to see if the sensor or wiring or meter is the problem?
 
   / Tachometer #2  
If you are talking about a Jinma 200 series with seperate gauges, and not the integrated dash, see this schematic and this wiring diagram.

Does the tach needle move at all? Does the light come on in the tach? Does the hour meter in the tach still work?
 
   / Tachometer #3  
first thing check Johns wire drawings. then

Check you're fuse wires first, you may have blown one? other thing look for power to the back of the gauge, if there is power there then look at the sensor on the left side just a head of the clutch there should be a "white/yellow" wire hooked up to the sensor on the clutch housing.


check those things, there is also a plug in rubber plug which is just down by the sensor check to make sure that is still plugged in. may have been pulled loose.?

check those things and post back to see what else we can help with.

Mark M /forums/images/graemlins/smile.gif
 
   / Tachometer
  • Thread Starter
#4  
IT'S ACTUALLY A DONGFENG WITH AN INTEGRATED GAGE PANEL. I'VE ALREADY CHECKED THE FUSES AND ALL THE CONNECTION OF THE WIRES BETWEEN THE PANEL AND THE SENOR ON THE FLY WHEEL HOUSING. HOW DO I CHECK THE POWER AT THE PANEL OR SENOR. I'M A ELECTRICAL IGNORAMOUS.
 
   / Tachometer #5  
The info that we posted above is for JINMA tractors, and probably don't apply to the DONGFE line different brand, same trouble shooting though. You will need a copy of the electrical drawing. look for incoming power to the gauge it;s self...

You will need a Meter. DMM can be bought for under 20 bucks for a ok one. at just about any tool store. analog ones too, though both are useable I prefer the Digital ones, (DMM = Digital Multi Meter)

One of them should be hot with Key on.
One will be Ground. check resistance to - on battery should be 0 ohmes.
Next remove connector that hooks to sensor, check resistance through the wire to make sure it is hooked up and not broken any where. look for wire colors and or numbering.
use the DC voltage range of 20 volts. start up tractor and check the output of the sensor. should output a spike of voltage, usually avout 3 volts but very quickly. this is where the Analog meter will show up the spike better than a DMM.

You can check that one side to ground if it is 2 wire or wire to wire. if it is one wire, go wire to ground.

try those things and let us know any results.

Mark M /forums/images/graemlins/tongue.gif
 
   / Tachometer #6  
Don't know much about the Jinma integrated dash, let alone the DF one. I would assume that it would have only one power and ground for the whole unit. If the other gauges are working, then fuse and power/ground wiring is OK. Check the sensor wiring as Mark suggested. Follow it through whatever connector to the back of the cluster. If the gauge set can be easily lifted out of the dash, check all connections on back. Also, try talking with a DF dealer to see if they can provide any more insight. Most likey, the tach can not be replaced seperatly from the other gauges in the dash.

PS: I attached the Jinma wiring diagram for the integrated dash. I have no idea how close it might be to DF.
 

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   / Tachometer
  • Thread Starter
#7  
Thanks for the info. I'll not be able to check it until the weekend. Will let you know how it goes.
 
   / Tachometer #8  
Got a question for you.. you seem to be pretty 'up' on the jinma wireing / gauges.

I looked at a jinma the other day ( homier ), and notice that while off, all the gauges were zeroed, but the temp gauge was over at the red area. I'm guessing temp gauge anyway... I was assuming it was measured in 'centigrade.
I don't remember if I saw an oil pressure gauge.. but in any case.. what would it have read in? psi or kg/s/cm ?
Or was this just how the gaugfe works.
thanks
Soundguy
 
   / Tachometer #9  
SGuy:

the gauges usually go to "0" when off, but if you turn the key off while the engine is running they "FREEZE" at that spot on my JM. leaving the tach setting at say 900 RPM. I'm trying to think if that aws all or jsut the tach that does that.? Oil gauge is in BARS and like 0 to something / I replaced mine with a good aftermarket dirrect reading mechanical gauge as i wasn't liking the short movement of the factory gauge which worked on & off. (loose ground I think or the sender was going south/) any how I had the 3 gauge cheapo odd lots kit setting in garage and stuck on the dirrect reading US gauge. now it shows 0 to 100 PSI. starts cold weather and can run at 100 PSI idle when it drops to 80 or less then I'll run her at warm start and running she runs with 40~60 PSIG.


I can relace the temp gauge too yet as it is a dirrect reading bulb type. (I'm not a fan of the cluster I like the sepperate gauges.)
As for the homier temp gauge not sure they may have wired it back wards, + to the - side of the gauge and that would make it read backwards I belive.?

anyhow hope that helps.

mark
 
   / Tachometer #10  
Hey all, I have a john deere 755 and the tach does not function. the hour meter does but the tach does not. Any Ideas or any experience trouble shooting this model or make? The tractor is a 1989 model. thanks.
 
 
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