I do not have any heat in my cat 256c skidder. I have check and have power at the temp control switch and the switch works like it should. I have cleaned the cores out and last year replaced the electronic control valve. Is there a fuse somewhere I could be missing that controls all this? thanks
If blower works, hvac fuse circuit is good. Check for voltage and signal at heater water valve. Could water valve actuator be failed?
When you say water valve actuator you mean the one in the pan down by the blower I assume? thanks
thank you by the way for the diagrams and such!!
This one might be a somewhat better illustration. Ref #8.
You said that you cleaned the core. The heater water valve is attached to the core.
Provided that you have a 480-8589 Water Valve it is available as a complete unit but you can also buy the Actuator separately under Part Number 563-0397. If you have an earlier P/N water valve such as 328-3317 the only option is to buy a complete assembly of the new Part Number.
thanks for diagram and info!! I talked to me dealer and now they say cat replaced the valve assembly on those from the originals. I am not sure why I wasnt told this before, but they say the new ones can be wired opposite of the originals so I may need to change the wire pins around. Seems like that would have good to know when I put the new one in. I will check it out one evening this week and let you know. Thanks so much for all the help.
That's weird. According to the P/N upgrade procedure (attached) it mentions nothing about any wiring changes.
Nige, that letter doesn't call out a 256C. I stole the schematic from a 262D, which may be the issue. The 256C uses a 266-2432, which is indeed replaced by the 480-8589, requiring a wiring update. This thread has all the info needed vvv HeavyEquipmentForums
Reading that link it would appear that we’ve been here before......
thanks guys. I will review the other thread and let you know.
Please pay special attention to the posts towards the end where Cat's deliberate mistake in an illustration within the REHS4097 modification procedure is unravelled and corrected......
reading your post I concluded Pin 1 in top right should be green, Pin 2 bottom right should be purple, Pin3 bottom left should be blank and pin 4 top left should be black. Is this the correct conclusion? thanks
Yes that is correct. Here's another copy of REHS4097 where I have edited the text for Steps 15 & 17 so that it corresponds with Illustration 10. TBH as was mentioned in that thread I would personally crimp the 9X-3402 Sockets on the 3 wires then plug them direct into the new water valve and test it before assembling everything into the 155-2271 Deustch connector and installing the wedge to hold it all in place.
thank you so much. will let you know what I find out. Have a great day!!!
So i got at it last night. I have power to the actuator but it is not opening and or closing the valve. looks like I need part number 563-0397. would you know by chance if that requires a rewiring like you described ? thanks
First thing you have to establish is whether or not you have the new design of water valve installed. The original 266-2432 Part Number of valve did not have a replaceable actuator. If that's what you have right now then you have to buy a complete new 480-8589 Valve and then you are into the re-wire as per the procedure in REHS4097. So first thing is to look closely at the existing valve for any sign of a Part Number. If you are lucky and have either the first update 328-3317 (279-0850) or the second update 480-8589 (563-0397) water vave installed then a separate actuator is available. Actuator Part Numbers in brackets.
I have the updated one. My actuator is the 279-0850. So I will not need a rewire kit? is that the correct assumption?
I think so, although 279-0850 is now cancelled and replaced by 563-0397. The update in REHS4097 was to install the 279-0850 in place of what was there before. If the back of your actuator looks like this with the 4-pins for the Deutsch connector in the corner it should be plug & play.
yeah, that is exactly what mine looks like. thanks for the help.