S/N: cat0226bemjh03996 I cant seem to get the continous flow function to work on my 226b. the aux.hydraulics work fine and i even did a continuity check on the cont. flow button that is in the left joystick. i followed the procedure to enable it as follows..... with machine running, lapbar down and park brake off, pull down on thumbwheel to activate aux. hyd., press and release the cont. flow button on the left joystick and immediately release the thumbwheel switch. i tried both directions with the thumbwheel but to no avail. any ideas?
Have you ever used continuous flow successfully before.?
no sir, its never worked since we got the machine.
Does the AUX system work when you roll the thumbwheel back/forward - provided of course that you have an attachment connected to the lines on the lift arm.?
yes it does
i checked all fuses in fuse panel under the seat, none were blown
Have you checked that Pin 7 on the ECM has continuity to ground when you press the continuous flow switch.?
no i have not. i will do that tomorrow and let u know. anything else i should check while i have the floorplate out?
If you look at the schematic the Cont Flow switch provides a path to machine frame ground from Pin 7 on the ECM via wire P993. Check that first. You could have a working switch but a break somewhere else in the circuit. AFAIK the same solenoid is energised for AUX as CONT Flow, the only difference being that in one instance it’s only energised provided that you are holding the thumbwheel over, in the other case it’s permanently energised. That’s the only thing I can think of to check.
awesome thanks alot much appreciated. once i check it ill post my findings
i just now got the floorplate off. sitting in the seat, its the ecm that is located on the left side correct?
ok nevermind the last question. its the ecm on the right side. the one on the left side doesnt have a pin 7. ANYWHO, i just checked it and the circuit is good. one probe on frame ground and the other on the red wire and pushed the button and my dmm made noise.
Well if the AUX function works when you roll the thumbwheel and the circuit from Pin 7 to ground is complete when the switch is pressed, the only thing left as far as I can see is the ECM but I would like to hear the opinions of others in that regard.
i was thinking the same thing. unless the procedure im using isnt correct.
You mean the procedure for engaging continuous flow as you described above.? No, that’s correct. Roll the thumbwheel and hold it there, press and then release the push-button, then within one second release the thumbwheel back to the centre position.
yea thats exactly how i did it
i wonder if there is a way to make the continious flow work, bypassing the ecm
Sorry that’s above my pay grade. I only deal with making ‘em work the way they’re supposed to……..
lol i hear ya. thank you tho for all your knowledge and wisdom. at leadt i now know where the problem is.
I’d really like someone else to chime in to confirm that the same solenoid valve is activated for both the AUX and CONT functions, just in a different way. EDIT: See if the attached helps.
thanx, i will look into this and let you know
the attached didnt help much. however, a question came to mind, in regards to the coil that holds the right joystick in the forward position. i believe its for float control. if that coil isnt connected, could it prevent continuous flow from working? work tool detent coil is what its called
Not AFAIK.
That's interesting. I thought the float coil was tied in with the interlock circuit. If it isn't connected then AFAIK, none of the hydraulics should work and you should have a flashing light on the console.
From the electrical schematic the implement pilot solenoid and the float solenoid are wired in parallel (via wires P988-OR & 975-WH) to the Interlock ECM. So if the pilot solenoid is powered up and working, as proved by the fact that the implement lift/tilt functions work, what negative effect on the AUX/CONT FLOW functions could the float detent solenoid not working possibly have.?
when the work tool detent coil went bad, i had flashing lights on console and the machine wouldnt move. but as soon as i unplugged it, the flashing lights turned off and machine functions just fine
Probably because it was shorting out the pilot solenoid and creating a Diagnostic Code. Disconnecting it resumed "normal service" as far as the Interlock ECM is concerned. Check it out on the electrical schematic.
yea you're right about that.... so i decided to remove the ecm and open it up. i figured if im gonna need a new one, i might as well have a look inside. i see 2 rows of transistors, one row on each end of the board. im gonna get the data sheets for them right now and test them with my DMM. im guessing one of them is connected to the cont. flow circuit. Ill post my findings, hopefully its just one of them that have gone bad.
I'm not 100% sure about your logic. You know that whichever component (transistor?) on the board that activates the solenoid for the AUX function is working when you roll the thumbwheel. As I see it the only difference between AUX and CONT functions is the input from the pushbutton that, combined with the thumbwheel input, causes the software programming in the ECM to activate the AUX solenoid permanently instead of in a momentary fashion as it does so long as you keep the thumbwheel held over.
yea you're probably right, but i figure its worth a shot.
I agree it is worth a shot. I was attempting to illustrate how I saw the logic of the ECM worked in an attempt to help you understand what was going on. ECMs are a black hole as far as I'm concerned, they either work or they don't.
yea i know what ya mean. for me they are just a bunch of components soldered to a board, so they can be unsolderd and tested lol
Should be a processor somewhere. That would be my #1 suspect.
well i managed to get my cat et software working again and connected to the ecm. i ran a "wiggle" test on the aux. hyd. system. its shows the status of all the controls and switches.it shows cont. flow switch status (open/closed) and cont. flow system status (on/off). something interesting i noticed is that with the engine running, sitting in seat, Lapbar down and park brake switch OFF, when i press the thumbwheel and the cont. flow switch, the switch status changes as it should (open to closed). but the cont flow system status doesnt change from OFF to ON. HOWEVER, if i set the park brake so the switch is ON and i press the thumbwheel and cont. flow switch, the cont. flow system status temporarily changed from OFF to ON. So its turns on but doesnt stay on....?
well i was mistaken about the cont. flow status not changing to ON when the parking brake wasnt set. but the underlying issue remains. the cont. flow turns on but wont stay on no matter what button combination i try.
I can't see it being anything other than a missing signal output from the processor side of the ECM to the appropriate solenoid depending in which direction you want the AUX flow to travel.
Check this out. These guys might be able to help you with the ECM - Link
thanx
PROBLEM SOLVED! it came to me last night while i was laying in bed. So apparently the thumbwheel switch wasnt returning to 0% at center. when at center it was at like - 24%. so i opened the switch and manipulated the springs and got it to return to 0% at center. now cont. flow works. thank you nige for all your wisdom and assistance. its much appreciated
Excellent that you cracked it but…… Do you think that the switch signal has been “off centre” ever since you got the machine.? I know you fixed it once by replacing the magnet.
quite possibly.... i wonder if thats what the calibration wire is used for