Discussion:
No hydraulics and only creep speed AO-4

Has a code AO-4, I've checked the fuses and contactors and looked over connections, I don't know what the code refers to because I loaned out my service manual and can't seem to get it back, any help will be greatly appreciated.
  • Posted 11 Apr 2013 07:33
  • By Tinkerdude
  • joined 11 Apr'13 - 6 messages
  • Florida, United States
Showing items 1 - 7 of 7 results.
Well I removed the heat sink assy, it was completely clogged, cleaned it real good and put back together, it worked for about a minute then coded again. So took it out again and connected 24v to one fan at a time, bottom fan worked great but top fan had low rpm's and got warm, so I'm going to go ahead and replace both of them, thanks for your help and will let you know how it goes when fans arrive
  • Posted 12 Apr 2013 04:58
  • By Tinkerdude
  • joined 11 Apr'13 - 6 messages
  • Florida, United States
Email is in there now
  • Posted 11 Apr 2013 12:51
  • By Tinkerdude
  • joined 11 Apr'13 - 6 messages
  • Florida, United States
Put your e-mail in your info.
  • Posted 11 Apr 2013 12:16
  • By rogeriwt
  • joined 10 Apr'07 - 323 messages
  • Massachusetts, United States
I'll check in the morning, but I don't know how to get dash into test mode, loaned out my manual and it never returned and its been several years since the last time its had any electrical issue, hope to get it back soon they're looking for it. thanks for the info, will let you know tomorrow
  • Posted 11 Apr 2013 11:43
  • By Tinkerdude
  • joined 11 Apr'13 - 6 messages
  • Florida, United States
When the truck is running do the fans turn on? Have you blown out the controller heat sink? It sounds like the cpu is overheating causing it to go into limp mode. It would be best to run the fans from the dash in test mode. That way you can be sure of wiring.
  • Posted 11 Apr 2013 11:25
  • By rogeriwt
  • joined 10 Apr'07 - 323 messages
  • Massachusetts, United States
Its only displaying that code, I had heard something about the cooling fan, I removed it today and applied low voltage to it from the battery like just three cells and it spun ok, it all started when the operator hit a bump 2 days ago, after its off for a bit it may run fine but just for a couple minutes then codes and only creeps with no hyd, I don't know but sort of suspecting the cpu board may have a fine crack through one of the foil patterns, what do you think.
  • Posted 11 Apr 2013 11:06
  • By Tinkerdude
  • joined 11 Apr'13 - 6 messages
  • Florida, United States
It's a code for the cooling fan, it doesn't specify which one. Are there any other codes?
  • Posted 11 Apr 2013 10:43
  • By rogeriwt
  • joined 10 Apr'07 - 323 messages
  • Massachusetts, United States

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