NH L220 Interlocks Have Me Defeated

[td25c]

Since it appears that Winter is finally over in upstate NY, I felt it was safe to remove my snow plow the other day. So, my SS started up just fine, shut the door, engaged my "seat belt defeat" switch (has a seat belt in place of lap bar), pressed the "operate" button on the panel, & WTF!!
The seat belt light is still blinking & the brake light is on steady, & of course all hydraulic functions are locked out because of this!!
After appropriate cursing, I removed the snow plow the hard way (with my FEL) & set about to try to diagnose the "locked" interlocks.

• Checked fuses - all OK.
• Buckled seat belt, thinking maybe my "defeat switch" was bad - no change.
• Unplugged seat belt interlock from the main harness behind the seat (uses a std. SAE plug), plugged in a SAE plug & pigtail into the harness, & positively closed the seat belt harness circuit (just like my "defeat" switch does) - no change. Just previously continuity tested the SAE plug & pigtail & it was fine.
• Decided that I needed to tilt the cab forward to check plug connections & such underneath. But the cab hold-down nuts are blocked by the vertical lift arms.
• So, tried to manually raise the lift arms with my FEL, but can't because the hydraulics are locked. The "emergency" hydraulic release in the cab appears to only work for lowering the lift arms, not for allowing them to raise.

In frustration, called my local NH service mgr., who suggested all the things I've already tried. Also, confirmed that the "emergency" hydraulic release usually only works to lower the lift arms, & even at that has to be held in position during the entire movement. So, even if it worked to allow the arms to be raised, it would be a 2 person job (one in the cab, another operating the manually-raise machine.
He suggested relieving the arm hydraulic pressure by cracking open one of the hydraulic connections on the lift are cylinders. Having checked them out, I see that they are all on the back side of the cylinders, not real easy to get at.

So, before I attempt what promises to be a very messy & knuckle-busting task of cracking open one of the hydraulic fittings, does ANYONE have any ideas!!!

By the way, have I mentioned how much I hate all the idiot interlocks on modern machines!!

Sure understand the frustration with the BS .

We did away with all that nonsense on the JD 8875 skid loader .

Now a man can hop in and operate it without any interruption .

We rented a 2016 model CTL and she let down pretty quick on some " safety BS " on the seat . Sorry fellers .... Aint interested .

http://nymag.com/daily/intelligencer/2018/06/trump-official-were-america-bitch-is-doctrine.html

 

[StumpyWally]

Gary...Eureka!!!...we can stop all further testing...I found the problem when I removed the entire cab liner from the back of the cab. The mice had built a colossal nest in the right back corner of the cab, under the windshield washer bottle (see photo below):


The connection cable for the seat belt switch passes right under the nest & back behind the HVAC unit to the right. Here is only the portion of the nest that I pulled out by hand (does not include the rest that I've vacuumed out):

The next photo shows the left back corner of the cab, where the connection cable plugs into a plug which is NOT shown on the electrical schematic:

Note the splice SP-102 above it. The splice looks fine, & I've verified that I have 12+v to ground at the red cable/pin in the plug.
The next photo shows the connection cable removed from behind the HVAC unit, & the mouse chew is clear. There was maybe one, very fine copper strand left in the red wire at the chew point.

The connection cable is actually a separate part, #84297138 REVB. I'll see if I can look it up, but I will probably just repair this one. With my luck, it will probably get chewed again sometime!!
Anyway, thank you so much for all your help. I hope this thread helps someone else in the future.

 

[GaryHoff]

Glad to see you found the issue. Great pictures, good job!!!

 

[StumpyWally]

Here is a update for everyone's info...
I found out the mouse-damaged harness is an available part...the new part #= 48151997, $10.88 at Messicks, $13.72 at my local dealer.
Nevertheless, I did repair my existing cable with soldered wire splices, shrink wrap, & a piece of new 3/8" loom around the affected area. My repaired cable looked like this before I re-installed in the machine:

My machine now works!!

 

[Kater]

Here is a update for everyone's info...
I found out the mouse-damaged harness is an available part...the new part #= 48151997, $10.88 at Messicks, $13.72 at my local dealer.
Nevertheless, I did repair my existing cable with soldered wire splices, shrink wrap, & a piece of new 3/8" loom around the affected area. My repaired cable looked like this before I re-installed in the machine:
View attachment 182688
My machine now works!!

Perhaps ammonia in a bottle with air holes to deter mice in future

I’m scared of mothballs...

Mouse x or ratx pellets fill mice with sodium till they die seemjngly peacefully as per directions (i watched a mouse in live trap on camera) 12 hours....

My tshirt seat cover was attacked in my Jcb 260 last winter i was horrifued to see

So much for Fresh cab....which loses its scent jn 30 days or if cold weather?

 

[Frogfarm]

StumpyWally,

Thank you for posting this information and pain for finding this mouse issue. I had the same mouse house issue in this huge used area on my 2013 L230 skid loader. The seat belt light just would not do anything until I removed the huge mouse nest and reconnected the seat belt wires that were eaten through..

Thankfully I found your post when searching and therefore the journey to solve was much shorter.

 

[Frogfarm]

StumpyWally,

Thank you for posting this information, work and pain for finding this mouse issue.

I had the same issue I just resolved, your posting helped greatly.

Thanks

Walt