DK40SE no start...pulling my hair out now.....

[MotorSeven]

2006 with 1400 hrs on it...........

For several months I have been chasing an intermittent no start. Turn key, dash lights and glow plugs come on, turn to start and nothing, no click, lights all stay on. Headlight and aux lamps stay bright before and after start attempts. Battery and connections are good(but I have not cleaned the ground to frame...that's today). I replaced all three relays on the firewall, the starter and the ignition switch....no change. A few years ago I replaced the neutral safety swith/poteniometer and I get proper N, 1 2 3 range light on dash. Jumped it with the Dmax yesterday and still had the same results.

I have a feeling it is a safety lock out, maybe the PTO? I do hear and feel the fuel shutoff click open when turning key. I have read all the threads, and maybe it's bad cables, but that seems hard to believe? Anyway, headed down to the barn to clean the ground....will report back later. I am even going to get out the shop manual. If anyone has any ideas, throw them out there as I am about to go nuts on this one.:confused3:

Rick

 

[woolyAcres]

These often come back to safety switches. Do you know what safety switches your machine has? I'd guess Neutral, Seat, and PTO. I'd start there. Had a similar problem on NH45. Turned out to be seat switch. Bugger to find but simple fix.

 

[MotorSeven]

Yep, prime suspect is the PTO safety and the Gear range neutral . Going over the manual today and the Cruise Control module has something to do with the start circuit also so I have to check that. Some I could not check alone since I had to be under the tractor holding the meter leads to the contacts while the starter switch needed to be engaged. I get a helper tomorrow.

Cleaned Neg ground and nada. I have 12.7V at the battery and at the starter, but nothing on the solenoid or exciter wire when in start position.

 

[JimR]

Yep, prime suspect is the PTO safety and the Gear range neutral . Going over the manual today and the Cruise Control module has something to do with the start circuit also so I have to check that. Some I could not check alone since I had to be under the tractor holding the meter leads to the contacts while the starter switch needed to be engaged. I get a helper tomorrow.

Cleaned Neg ground and nada. I have 12.7V at the battery and at the starter, but nothing on the solenoid or exciter wire when in start position.

Also check your seat switch and brake switch.

 

[k0ua]

Also check your seat switch and brake switch.

There is no seat switch or brake switch that effects engaging of the start relay on the firewall.. Only the Neutral safety potentiometer (not a switch) and the PTO switch,

 

[MotorSeven]

James, it looks like the same part that failed a few years ago....Range Shift Indicator. Im perplexed because according to the dash lights its working properly, but it failed the ohm test with a 'zero' reading.
Ordered a new one(again) and am gonna try your trick of drilling the housing and spraying the inside with a deox.

Here is my old thread on it:
https://www.tractorbynet.com/forums.../302554-dk40se-hst-neutral-safety-switch.html

 

[MotorSeven]

Oh, and the pto switch passed the ohm test.

 

[k0ua]

James, it looks like the same part that failed a few years ago....Range Shift Indicator. Im perplexed because according to the dash lights its working properly, but it failed the ohm test with a 'zero' reading.
Ordered a new one(again) and am gonna try your trick of drilling the housing and spraying the inside with a deox.

Here is my old thread on it:
https://www.tractorbynet.com/forums.../302554-dk40se-hst-neutral-safety-switch.html

Hm...curious. So when you removed the pot, it measures 0 ohms across all terminals? Very curious.

 

[MotorSeven]

Well, after i removed the potentiometer and double checked it I realized we had the multi-meter set wrong and on the correct setting it tested good.
Back to square one....

 

[MotorSeven]