Workmaster 33 in "Safe Mode"

   / Workmaster 33 in "Safe Mode" #1  


New member
Dec 19, 2022
New Holland Workmaster 33
We have a Workmaster 33 bought in 2017 which now has 120 hours. The red exclamation point engine warning light and the regeneration lights are blinking and the tractor won't go above 1800 RPM. I have read that this may be due to failure to regenerate the DPF and/or there may be error codes stored in an ECM. I have warmed it up and tried to force a regen cycle with no luck. It did start one, only to stop about 20 minutes later. I've worked on cars for a long time, but I'm new to tractors. What would be the course of action to get back up and running?
   / Workmaster 33 in "Safe Mode" #2  
Codes on dash? or have a reader that will pull codes from that ECM? Could be a few things if it has a DOC before the DPF it could be that the DOC is not going into a burn cycle (bad DOC injector or plug). DFP too clogged to clear, pressure sensor fault, EGR valve or ECM. Just like the newer cars without codes it is just a parts swapping exercise that is expensive and frustrating.
If your DPF (and/or DOC) is clogged you can soak it a pool acid batch for a 20 min, 1 part acid 4 parts water. Then rinse WELL, that should remove ash deposits without hurting the DPF.
   / Workmaster 33 in "Safe Mode"
  • Thread Starter
There are no codes on the dash. Just the red engine warning light and the DPF light. Both are blinking.
   / Workmaster 33 in "Safe Mode"
  • Thread Starter
Thanks for the replies. I may have misspoke. I suppose the blinking lights are the error lights.

I started it up and ran it for a few minutes and it went into regen mode for about 10-15 minutes, then stopped. The engine error light is blinking once every two seconds and the DPF light is blinking once a second. After the regen stopped, the DPF light went back to blinking once a second. I tried to force another regen, but it wouldn't work.
   / Workmaster 33 in "Safe Mode" #6  
It sounds like it is time to call your dealer.

Did you purchase it new, if not then your closest dealer?

There maybe some warranty remaining on it?

Hope they are able to get it figured out for you.
   / Workmaster 33 in "Safe Mode" #7  
Best I can tell the blinking light means it thinks it needs a regen still. Now why is the question to be answered. We're back to my first post, without knowing what is not right per the ECM it's a WAG. It could be a legit DOC/DPF problem or a faulty input. 170 hrs is not even broke in yet, I would check for rodent damage, wires rubbing on the radiator support, connections on the DOC/DPF unit and EGR valve.
These systems are similar to the systems used on the European small diesel cars, you learn a lot by reading about the them as well. BTW LS made the workmaster for NH so things from that era LS apply to your tractor might check that forum as well.
   / Workmaster 33 in "Safe Mode"
  • Thread Starter
The only update I have is that it starts up with the same engine warning light and DPF lights blinking. Once warmed up, it goes into a regen cycle. However, I don't smell the usual burning smell associated with regen and the regen cycle never seems to end. I just ran it for two hours most of the time doing work (moving snow and gravel) and then parked it for about 30 minutes. I finally gave up and turned it off.
   / Workmaster 33 in "Safe Mode" #9  
WIth that I would guess that the DOC just before the DPF does not go into the burn cycle. I believe there is a fuel injector and glow plug in DOC to get it burning. If either one is not working it would never really perform a regen due to lack of heat. I'm not the expert on this stuff all new to me as well, just got my first diesel with that crap.
   / Workmaster 33 in "Safe Mode" #10  
I have a 2016 Workmaster 33 with 900 hours and the EXACT same issue. I took it to the dealer and had the DPF cleaned about 16 tractor hours ago. I run DPF additive, read everything on regen in the operator manual, and run the tractor at 1,800 RPM and let it finish regen cycles. It went into safe mode last week. I cleaned the DPF myself via acid bath but am stuck in safe mode. Does anyone know if safe mode will clear on its own? I bought the ELM327 OBD and a cable to see if I can clear the code. I’ve had the dealer clean the DPF twice which is costly and laborious for me. I’m also thinking about the burner issues listed above but would like to know how to test for faulty components. The glow plug in the burner is $200 so I'd like to test it before buying a new one. Has anyone else had to replace the glow plug in their burner?
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