I have a CAT 257B. It has this weird issue where it will start up and run fine, but when you turn the key off, the machine doesn’t shut off. It acts like the key is still in the on position. I can get the machine to shut off by unplugging a plug, which works fine but obviously I want the key to work. When I get the machine shut off, then plug the plug back in, the parking light on the dash comes on and the hydraulic pressure light comes on (this is the same as when the key is on but machine not running). I unplugged the ignition switch when this was happening but that didn’t change anything. Wondering if there might be a relay somewhere that could cause this? Otherwise does anyone else have any clues? There is quite a few relays in the engine bay but unlabeled, no idea what they are for.
Please post a Serial Number. That will get you better information.
Can you post a picture of your fuel shut off solenoid?
I don’t have an image of the actual thing on the machine, but it is #15 in this diagram. A 12v shutoff. I could be wrong but I’m not sure if this is the problem, because the dash itself stays on too as if I had the key on. I don’t think the fuel shutoff would do that?
Ah, okay, didn’t realize that you still had voltage to front after key off.Hopefully someone can post a schematic, so we can see where your ignition relay is.
Yep, unfortunately do. I was thinking maybe a relay is sticking or something. Otherwise possibly a short but wanted to get some knowledge on the workings of the electrical of this thing before hunting a short down.
As previously requested a Serial Number is the key to that.
My apologies, thought I replied to your previous comment with it. SLK00874.
No worries. You will need the attached illustrations for a start, plus an electrical schematic. Keep an eye on your messge inbox.
Thanks a lot! Will do. What the heck is a cold start relay?
That's the one that gives the fuel rack an extra shove to aid starting when the coolant temperature is low.
if you can find your relays, when you shut the key off and you still have power, I would just pull on each relay till power is gone. Then you have identified the stuck relay.