New holland l230 park brake solenoid?

[NITRO]

Hi, i need some help with my 2012 L230 skidsteer. Symptoms: error code 4431 After about 70 hrs on the hr meter the display would sometimes beep after morning startup as soon as the operate button was pushed. A yellow dash light that looks like an upside down capital letter T. It would beep and display that light just after button was pushed and i could feel the park brake releasing. The light would stay on for a second or two then go out and i would use machine as normal. The beep and light has become more frequent after startup which is telling me something funny is going on as it never done it when i bought the machine with 16 hrs on it. Today, i was turning a windrow and the park brake light started flickering on and the upside down T light also cane on along with a beep but the machine still was driving fine. I turned it off and re started it but as soon as i press operate button the park light stays on along with the upside down T. If i press the park button the park light stays on but wheels wont drive. If i press operate again it will move off but park light remains on aling with fault code 4431 and the upside down T light staying on. Ive tilted cab and waiting on your instructions. Thanks

 

[NITRO]

Put cab back down and started it up and everything seemed normal, done 5 minutes work and then it beeped park light comes on along with upside down T light and aux overide flashing too. Machine keeps going while lights are on. If i press park button the lights remain lit but it the park brake comes on. If i press operate again it will drive off fine and hydraulics work but the park and T light stay on? Any ideas?

 

[NITRO]

Put cab back down and started it up and everything seemed normal, done 5 minutes work and then it beeped park light comes on along with upside down T light and aux overide flashing too. Machine keeps going while lights are on. If i press park button the lights remain lit but it the park brake comes on. If i press operate again it will drive off fine and hydraulics work but the park and T light stay on? Any ideas?

Tried machine again, started it then press operate button. Park light and the upside down T comes on but if i rev engine up to 2000 rpm the lights go out? Lol wtf is wrong with it Haha.

 

[NITRO]

Tried machine again, started it then press operate button. Park light and the upside down T comes on but if i rev engine up to 2000 rpm the lights go out? Lol wtf is wrong with it Haha.

Changed hydraulic oil filter. Still the same fault code 4431. Machine has 116 hrs on it.

 

[NITRO]

Changed hydraulic oil filter. Still the same fault code 4431. Machine has 116 hrs on it.

Ok, got my hands on a few pages from the service manual and it has a procedure to fix the error 4431. It says its a disagreement between the park brake pressure swirch and the park brake solenoid. Its either: Low charge pressure, open or shorted wire in the circuit, park brake solenoid failure, park brake pressure switch failure, or a fail of the UCM. Ive found the block that has the switch and solenoids on it and will try to do some tests on that with the multimeter to try get some clues. Part of the troubleshooting procedure is to connect an electronic service tool and another part is to check charge pressure. I cant do the electronic service tool part but if i can find where to test the charge pressure i can try to hook up a gauge and see the pressure. So where can i plug in my gauge to check the charge pressure? Thanks

 

[Tazza]

Ok, got my hands on a few pages from the service manual and it has a procedure to fix the error 4431. It says its a disagreement between the park brake pressure swirch and the park brake solenoid. Its either: Low charge pressure, open or shorted wire in the circuit, park brake solenoid failure, park brake pressure switch failure, or a fail of the UCM. Ive found the block that has the switch and solenoids on it and will try to do some tests on that with the multimeter to try get some clues. Part of the troubleshooting procedure is to connect an electronic service tool and another part is to check charge pressure. I cant do the electronic service tool part but if i can find where to test the charge pressure i can try to hook up a gauge and see the pressure. So where can i plug in my gauge to check the charge pressure? Thanks

I don't know where the sender would be, but it should be a round screw in unit. Check for parts lik this taht screw into the hydraulic system around the pump or filter, hopefully one of them is the one you want.
Senders to go bad quite often, hopefully that is the issue. If it looks at all wet, i'd get a new one.
The other issue is, some new senders are not just an on/off switch like we have on car engine oil pressure ones, they will show what pressure it is to the ECU, so you can't test them like th eolder ones. If it has 3 wires, there is the possibility it is not just on/off.
Sorry i haven't responded sooner, i have never worked on a machine like this so have no idea where to start. Hopefully Mike10 will pop in, he knows his NH machines inside and out.

 

[NITRO]

I don't know where the sender would be, but it should be a round screw in unit. Check for parts lik this taht screw into the hydraulic system around the pump or filter, hopefully one of them is the one you want.
Senders to go bad quite often, hopefully that is the issue. If it looks at all wet, i'd get a new one.
The other issue is, some new senders are not just an on/off switch like we have on car engine oil pressure ones, they will show what pressure it is to the ECU, so you can't test them like th eolder ones. If it has 3 wires, there is the possibility it is not just on/off.
Sorry i haven't responded sooner, i have never worked on a machine like this so have no idea where to start. Hopefully Mike10 will pop in, he knows his NH machines inside and out.

I have found a block on the left side of machine which has 3 solenoid valves in a row along with a brake pressure sender and a charge pressure sender switch. The middle solenoid is the brake and the front one is the 2 speed, not sure about the one at the back. The brake and pressure switches have 2 wires, i disconnected those and plugged them back in. I tapped everything with a spanner and found 2 earth wires on a chassis post that dissapeared into harness near the switch wires so cleaned that too. No luck, I have some diesel comp test gauges here that i may be able to adapt to check charge pressure but wouldnt have a clue where to test the charge pressure. My plan of attack next will be to try figure out if the brake switch is faulty so i will try a continuinity test across the wires when turned off and then somehow try to get a test with it all running which may require a small block under cab and a mate sitting in there at an angle lol.

 

[Tazza]

I have found a block on the left side of machine which has 3 solenoid valves in a row along with a brake pressure sender and a charge pressure sender switch. The middle solenoid is the brake and the front one is the 2 speed, not sure about the one at the back. The brake and pressure switches have 2 wires, i disconnected those and plugged them back in. I tapped everything with a spanner and found 2 earth wires on a chassis post that dissapeared into harness near the switch wires so cleaned that too. No luck, I have some diesel comp test gauges here that i may be able to adapt to check charge pressure but wouldnt have a clue where to test the charge pressure. My plan of attack next will be to try figure out if the brake switch is faulty so i will try a continuinity test across the wires when turned off and then somehow try to get a test with it all running which may require a small block under cab and a mate sitting in there at an angle lol.

You should be able to get away with a smaller gauge than a diesel compression tester, it should be around the 120PSI mark.
If you remove one of these senders, you should be able to screw in a gauge. Even if you have one at a filter, it should all be at charge pressure.

 

[NITRO]

You should be able to get away with a smaller gauge than a diesel compression tester, it should be around the 120PSI mark.
If you remove one of these senders, you should be able to screw in a gauge. Even if you have one at a filter, it should all be at charge pressure.

I found the problem. Tested the charge pressure at the brake lines and there is 400psi while machine is running in operate mode at idle and zero psi when park brake is applied so that means the park brake solenoid is working and allowing pressure into brakes and brake switch circuit. I spliced into both wires of the brake switch and tested for continuinity across the switch at zero and 400 psi and both tests revealed open circuit. When i touched the wires together in operate mode the fault cleared. I then turned the park brake on and touched wires together and fault reapeared in park mode instead of the usual fault only showing in operate mode. The ecu expects to see switch pressurised and continuation in operate mode and open circuit across the brake switch in park mode. The brakes release at 218 psi and the brake switch is rated at 225 psi but even with 400 psi the switch fails to do anything so I rang the dealer, went through my diagnostics with them and they are sending me a new switch under waranty and i will put in on. It costs $270 for the switch and the dealer is 600km away so finding the fault myself saved a bit of time and freighting machine back to dealer. Thanks for the help cheers,

 

[desras]

Hi, i need some help with my 2012 L230 skidsteer. Symptoms: error code 4431 After about 70 hrs on the hr meter the display would sometimes beep after morning startup as soon as the operate button was pushed. A yellow dash light that looks like an upside down capital letter T. It would beep and display that light just after button was pushed and i could feel the park brake releasing. The light would stay on for a second or two then go out and i would use machine as normal. The beep and light has become more frequent after startup which is telling me something funny is going on as it never done it when i bought the machine with 16 hrs on it. Today, i was turning a windrow and the park brake light started flickering on and the upside down T light also cane on along with a beep but the machine still was driving fine. I turned it off and re started it but as soon as i press operate button the park light stays on along with the upside down T. If i press the park button the park light stays on but wheels wont drive. If i press operate again it will move off but park light remains on aling with fault code 4431 and the upside down T light staying on. Ive tilted cab and waiting on your instructions. Thanks

 

[Tazza]

I found the problem. Tested the charge pressure at the brake lines and there is 400psi while machine is running in operate mode at idle and zero psi when park brake is applied so that means the park brake solenoid is working and allowing pressure into brakes and brake switch circuit. I spliced into both wires of the brake switch and tested for continuinity across the switch at zero and 400 psi and both tests revealed open circuit. When i touched the wires together in operate mode the fault cleared. I then turned the park brake on and touched wires together and fault reapeared in park mode instead of the usual fault only showing in operate mode. The ecu expects to see switch pressurised and continuation in operate mode and open circuit across the brake switch in park mode. The brakes release at 218 psi and the brake switch is rated at 225 psi but even with 400 psi the switch fails to do anything so I rang the dealer, went through my diagnostics with them and they are sending me a new switch under waranty and i will put in on. It costs $270 for the switch and the dealer is 600km away so finding the fault myself saved a bit of time and freighting machine back to dealer. Thanks for the help cheers,

Lets hope that fixes it, nice of your dealer to step up and send you a new switch.