Fairfieldcounty
Active Member
I powered them down yesterday and did that, I will have to try it tomorrow now that I have power there, the float function does work. Beats me, we’ve been trying to figure it out for 2-3 days now with no luck.
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CAT 930H RIDE CONTROL NOT WORKING
- Thread starter Fairfieldcounty
- Start date
I powered them down yesterday and did that, I will have to try it tomorrow now that I have power there, the float function does work. Beats me, we’ve been trying to figure it out for 2-3 days now with no luck.
Nige
Senior Member
I think you can do it, maybe not exactly the way the book says (which uses ET) but it ought to work.
The test in the manual for the Ride Control Accumulator involves powering up the Ride Control solenoid - Post #16 on previous page.
Exactly as I suggested back then, and with the engine stopped, apply battery voltage to Pin A (wire # A520 Blue). That will pull in the relay and energize the solenoid. Make sure that happens, then do the following: -
1. Start the engine.
2. Raise the bucket about half-way. Tilt the bucket as far forward as it will go.
3. Lower the bucket to the ground. Continue to apply downward pressure. Try to lift the front wheels off the ground.
4. If the accumulator is charged correctly the front wheels will not lift off the ground.
The test in the manual for the Ride Control Accumulator involves powering up the Ride Control solenoid - Post #16 on previous page.
Exactly as I suggested back then, and with the engine stopped, apply battery voltage to Pin A (wire # A520 Blue). That will pull in the relay and energize the solenoid. Make sure that happens, then do the following: -
1. Start the engine.
2. Raise the bucket about half-way. Tilt the bucket as far forward as it will go.
3. Lower the bucket to the ground. Continue to apply downward pressure. Try to lift the front wheels off the ground.
4. If the accumulator is charged correctly the front wheels will not lift off the ground.
Fairfieldcounty
Active Member
That worked. The wheels did not lift off the ground when we applied power to pin A at conn 53 plugged in. With it unplugged it did not work. How do i test the pressure switch? I’m starting to think it is malfunctioning but it is sending signal when the machine is in motion.
Nige
Senior Member
The spec is on that electrical schematic I sent to you.
Normally closed switch.
Opens @ 32.6psi MAX with rising pressure.
Closes @ 29.7±2.9 psi with falling pressure.
You may have to get a bit creative about how you test it.
Normally closed switch.
Opens @ 32.6psi MAX with rising pressure.
Closes @ 29.7±2.9 psi with falling pressure.
You may have to get a bit creative about how you test it.
Fairfieldcounty
Active Member
still scratching my head on the switch because testing it is difficult without pressure however. I energized 976 OR at the relay and have power at 976 OR at the pressure switch. I also have power at the blue wire at the pressure switch at the same time. I should only have a signal through the blue wire when the switch is open with pressure correct?
Last edited:
Nige
Senior Member
Power comes down wire 976 OR from the Relay (when the relay is pulled in as per signal from the ECM) located in the fuse box.
976 OR also supplies power to Terminal 1 of the Ride Control Relay located by the solenoid valve.
The Pressure Switch is normally closed (opens with rising pressure) so you should have power on wire A520 BU all the time the switch is closed, in which case it will not be energized.
A520 BU from the pressure switch is also the signal wire for the operating coil of the relay (terminal 5) - the other side of the operating coil (terminal 2) is grounded. So when A520 is energized the relay is pulled in. Effectively as soon as the pressure rises and opens the switch the Relay should deactivate.
How are you testing the system.? Engine off or engine running.?
976 OR also supplies power to Terminal 1 of the Ride Control Relay located by the solenoid valve.
The Pressure Switch is normally closed (opens with rising pressure) so you should have power on wire A520 BU all the time the switch is closed, in which case it will not be energized.
A520 BU from the pressure switch is also the signal wire for the operating coil of the relay (terminal 5) - the other side of the operating coil (terminal 2) is grounded. So when A520 is energized the relay is pulled in. Effectively as soon as the pressure rises and opens the switch the Relay should deactivate.
How are you testing the system.? Engine off or engine running.?
Fairfieldcounty
Active Member
Key on engine off. We do not have power all the time at the blue wire with key on engine off not engine running. Should it only have power when ride control is active or at all times? Per schematic it seems it should be powered at all times. I energized the relay manually with the machine running and the booms drops to position as if the accumulators are charged and working properly. I believe I have. Working issue with the blue wire if it should be powered all the time
Nige
Senior Member
I don’t have the schematic in front of me but working from memory the relay in the fuse box should energize with the key on AND a Ride Control signal from the ECM. Key on supplies system power to the relay, the signal from the ECM energizes the coil and pulls the relay in.
If the above happens, wire 976 will be energized.
The pressure switch is normally closed so with engine stopped and power on 976 OR, A520 BU will also be energized which will pull the 2nd relay in.
As soon as the pressure rises the pressure switch will open and the contacts of the 2nd relay should also open because it has lost the power to the coil that was supplied by wire A520.
If you have a DMM put it across the terminals of the pressure switch with the engine stopped and check the continuity. It should measure close to zero ohms. Then start the engine and do the same test. This time it should be open circuit indicating that rising pressure has opened the switch.
If the above happens, wire 976 will be energized.
The pressure switch is normally closed so with engine stopped and power on 976 OR, A520 BU will also be energized which will pull the 2nd relay in.
As soon as the pressure rises the pressure switch will open and the contacts of the 2nd relay should also open because it has lost the power to the coil that was supplied by wire A520.
If you have a DMM put it across the terminals of the pressure switch with the engine stopped and check the continuity. It should measure close to zero ohms. Then start the engine and do the same test. This time it should be open circuit indicating that rising pressure has opened the switch.
Fairfieldcounty
Active Member
ok so here's where I'm at... key on engine off - no power at 976OR and A520BU at pressure switch before signal from ecm? PRIOR to the relay being energized via signal from ecm should I have power at A520BU at pressure switch?
-Engine running, machine in motion, FUSE BOX relay pulls in and 976OR is energized, 976OR signal present at pressure switch. A520BU energizes and second relay clicks and sends power to solenoid valve.
the system began working after replacing the relays, suppressor however it only works when the boom is bottomed out not if is raised at all and provides no damping. it raises it a few inches but again, provide no damping.
-Engine running, machine in motion, FUSE BOX relay pulls in and 976OR is energized, 976OR signal present at pressure switch. A520BU energizes and second relay clicks and sends power to solenoid valve.
the system began working after replacing the relays, suppressor however it only works when the boom is bottomed out not if is raised at all and provides no damping. it raises it a few inches but again, provide no damping.
Nige
Senior Member
Based on those symptoms I think you need someone with nitrogen charging tooling to check the pre-charge pressure in the Ride Control accumulator.