Glow plug light not working

Jsaon41

New member

Equipment
L35
Oct 26, 2016
1
0
0
Haddam Ct.
The other day I went to start my L35 and the glow plug light didn't come on. The machine started without issue but I thought it odd. There wasn't the relay click or drop out either. The other normal prestart dash lights came on but no glow plug. Is this the machines way to tell me the glow plug is shot? Or could it be a relay buried under the dash? Is there a way to test the plug?
Any thoughts?
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
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113
Sandpoint, ID
It's not one Glow Plug it's 3 on your model (one per cylinder).
The issue could be as simple as a blown fuse, bad relay, burned out glow plug or plugs, bad wiring.
If your normally hearing a click of a relay when the glow plug light is on, and right now your not, then I would focus on a blown fuse and then the possibility of bad relay or wiring. ;)
 
Last edited:

lugbolt

Well-known member

Equipment
ZG127S-54
Oct 15, 2015
3,771
871
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Mid, South, USA
The glow plugs on those tractors run off of a controller behind the dash. The controller works off of the coolant temp sensor. If coolant temp is cold, the controller senses it and triggers the glow plug relay to stay on longer than if it was hot coolant.

That said, it's not uncommon for the controller to die. Sometimes the relay, but more frequently the controller. To my knowledge, there is not a tried-and-true test for it. When I diagnose one, I'll test the relay, wiring, and the coolant temp sensor. If all those are ok, the controller's usually shot.
 

seann

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Equipment
B6200
Aug 30, 2010
19
0
1
Markdale, Ontario
The glow plugs on those tractors run off of a controller behind the dash. The controller works off of the coolant temp sensor. If coolant temp is cold, the controller senses it and triggers the glow plug relay to stay on longer than if it was hot coolant.

That said, it's not uncommon for the controller to die. Sometimes the relay, but more frequently the controller. To my knowledge, there is not a tried-and-true test for it. When I diagnose one, I'll test the relay, wiring, and the coolant temp sensor. If all those are ok, the controller's usually shot.
Do you know where the controller is on an RTV 1140 and a part #?
 

Technical Ted

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Equipment
L3560/cab LA805 loader LandPride RCF2060 rotary cutter, HLA hyd angle snow blade
Jul 2, 2016
105
0
16
Dansville NY
Does anyone know how cold the coolant has to be for the glow plugs to activate? I've got a L3560 and have never seen the glow plug symbol on my dash, but I don't think I've ever stored it where it was less than ~45 degrees F.

Thanks,
Ted
 

sheepfarmer

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L3560, B2650, Gator, Ingersoll mower
Nov 14, 2014
4,279
500
113
MidMichigan
Does anyone know how cold the coolant has to be for the glow plugs to activate? I've got a L3560 and have never seen the glow plug symbol on my dash, but I don't think I've ever stored it where it was less than ~45 degrees F.

Thanks,
Ted
I think they may be active during the time that the welcome Kubota stuff is flashing across the display, and you don't see the glow plug symbol to wait longer until it is pretty cold, I think it was 18F or so. You may never see yours if the tractor is inside above 45.
 

dmac

New member

Equipment
M5040
Dec 7, 2016
2
0
0
Alabama
would that temperature sensor cause my control relay for the glow plugs to be missing a ground. it has 12 volts when I turn the key to the on position but no ground.
 

CountryBumkin

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BX2370 w/LA243, Bucket, Grapple, QA Pallet Forks, 60" MMM, rear blade & rake
Sep 27, 2015
568
1
0
Central FL
would that temperature sensor cause my control relay for the glow plugs to be missing a ground. it has 12 volts when I turn the key to the on position but no ground.
I don't know the specifics on your tractor model, but it is possible that that coolant sensor is a actually a coolant "switch" (open when hot, closed when cold) in that case the relay could use the switch as its ground.
 

Technical Ted

Member

Equipment
L3560/cab LA805 loader LandPride RCF2060 rotary cutter, HLA hyd angle snow blade
Jul 2, 2016
105
0
16
Dansville NY
I think they may be active during the time that the welcome Kubota stuff is flashing across the display, and you don't see the glow plug symbol to wait longer until it is pretty cold, I think it was 18F or so. You may never see yours if the tractor is inside above 45.
Thanks!
Ted