Discussion:
Hyster J40XMT2 Computer and lights on with key off

Thanks in advance for the help.
I have my Hyster J40XMT2 3 wheel 48v forklift and it has been doing some weird stuff lately.
When the key is off, the rear LED lights stay on, I figured it was a bad relay somewhere but I was just replacing the steering pot (Thanks for this forum for help with that btw) and noticed that the steering pot gets a constant 4.3V feed regardless of key position.

Is there something I should look for? there are few contactors on this this unit and none appear welded and none have continuity when off.

Its frustrating as I do not use the truck often and it drains the battery over time.
  • Posted 7 Oct 2018 01:06
  • By Tomayr
  • joined 7 Oct'18 - 7 messages
  • Ontario, Canada
Showing items 1 - 6 of 6 results.
Thanks in advance.
  • Posted 11 Oct 2018 00:24
  • Modified 12 Oct 2018 23:46 by poster
  • By Tomayr
  • joined 7 Oct'18 - 7 messages
  • Ontario, Canada
What is your Email address?
  • Posted 10 Oct 2018 23:39
  • By BREWSKI
  • joined 10 Jan'12 - 1,699 messages
  • Nebraska, United States
Is there any chance you can post or supply me with the wiring diagram? I am wondering if I can trace back the circuit in case it has rubbed through somewhere along the way.
Thanks,
Tom
  • Posted 9 Oct 2018 00:35
  • By Tomayr
  • joined 7 Oct'18 - 7 messages
  • Ontario, Canada
ok the truck has a DC/DC converter but that only supplies the power to the circuit, we know it is working because the lights are on.
There is a brake switch at the brake pedal, check the switch and make sure it is not shorted or adjusted wrong.
Quite a few machines use a relay but i do not see one in the circuit on this one.
  • Posted 8 Oct 2018 22:52
  • By swoop223
  • joined 23 Mar'12 - 3,691 messages
  • North Carolina, United States
You've been swooped!
swoop223@gmail.com
Absolutely, Thanks for your help.
Serial is H160N02779Y

It does appear to have a DC/C converter.

Thanks!
  • Posted 7 Oct 2018 23:56
  • By Tomayr
  • joined 7 Oct'18 - 7 messages
  • Ontario, Canada
can you give us a serial number?
my first thought was same as yours, maybe a stuck reverse light relay. But then i thought about a possible problem with a DC/DC converter that some units may have depending on when they were mfg'd. (hence why the serial number is important).
Then some units have the truck manager module control these things

So, serial number?

thanks
  • Posted 7 Oct 2018 22:49
  • By swoop223
  • joined 23 Mar'12 - 3,691 messages
  • North Carolina, United States
You've been swooped!
swoop223@gmail.com

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