CAT 287B: Starts but both joysticks non-responsive.

2006 CAT 287B tracked Loader SN: ZSA02465

Issue: Left Joystick (forward/reverse/turn) non-responsive and Right Joystick (up/down/tilt) non-responsive.

Symptoms: Parking Light Indicator light flashing after engine starts and park switch pushed to disengage.

Background:
seat/Armrest light was also flashing but after I replaced "brake Solenoid", only brake light flashes.
Old brake Solenoid PN:4303612B showed 4.5ohms across the coil (<5) so i replaced it.
New solenoid PN259-8194, has same 4.5 ohm reading across the coil. So I believe old solenoid is good and the 5 ohm limit I used is too high.
There are 3 hydraulic valve solenoids I can access under the seat when cab is tilted up. I replaced the one on the left (when seated looking forward)
I assume this is the "parking" solenoid.
Resistance of all 3 solenoid is 4.5 ohm
The other two solenoids are on the right, both on the same hydraulic block assembly. One forward, the other aft.
I have not found a drawing good enough to confirm solenoid functions.

I believe seat switch and arm rest switch are okay, because machine starts when seat switch is depressed and arm rest magnets are in alignment. The engine will not start if either of these switches not depressed or not in alignment, respectively.

None of the 3 coils receive power when engine is running, and joysticks are manipulated.
I believe the safety lockout system has a fault and is not allowing power to the solenoids so no hydraulic pressure is available to the joysticks.

ECM's are under the floor panel. The foot throttle makes it hard to remove the floor panel and gain access to the ECM's. By partially dismantling the throttle linkage I have been able to lift and block one edge of the floor panel to have some access to the ECM's. But i will have to unbolt them from the front wall and pull them and the harnesses up and back to be able to work on them.

Objective: The machine is in an unsafe location.
I would like to bypass the safety system free up the hydraulics and drive it .5mi on my property to my shop so I can work on it.

Question 1: If I run 12V from a temporary 10 amp circuit with a switch to the positive lead on the parking solenoid coil and connect the other coil lead to ground, will this enable the hydraulic system when the machine is running, driver seated, arm rest down and temporary switch closed?

Question 2: what do you think the issues is?

Question 3: how would you go about finding and fixing it?

Comments and suggestions are welcome.

Thank you for responding.

Nige
Thank you for the latest schematics.

Park Solenoid:
They indicate the parking solenoid should be PN 195-9700 and coil resistance should be 10 ohm +/-.5
and at the location I thought. However, the dealer sold me PN 259-8194 and coil resistance is 4.5
Could this be an issue?

Park Switch:
Terminal 3 of Park Break Switch has 12V when engine is running and connects with terminal 2 when switch is held down. But will not stay connected without maintaining pressure on switch.
Terminal 8 shows no voltage when grounded, engine running or not.
Incoming wire is 614-CN89 PU 18. I'm not sure how to tell where this originates, to trace the issue.
I assume terminal 8 should be hot with engine running or with engine off.
There is infinite resistance between terminals 7 to 8, engine running, or not / Switch depressed or not.
Not sure if this means switch is bad or if current is required at 8 to close contact.
Looks like 7 t0 8 is for indicator lamp. Could a burnt-out lamp in the park switch disable the joysticks?

Thanks

jmchugh1958 said:

There are 3 hydraulic valve solenoids I can access under the seat when cab is tilted up. I replaced the one on the left (when seated looking forward)
I assume this is the "parking" solenoid.
Resistance of all 3 solenoid is 4.5 ohm
The other two solenoids are on the right, both on the same hydraulic block assembly. One forward, the other aft.
I have not found a drawing good enough to confirm solenoid functions.

Click to expand...

Try posting a photo of what you're looking at.

See the attachment which is a description of how the Interlock System operates.

jmchugh1958 said:

They indicate the parking solenoid should be PN 195-9700 and coil resistance should be 10 ohm +/-.5

Click to expand...

195-9700 is the correct Part Number for the parking brake solenoid for ZSA02465. It is part of the 208-5681 Parking Brake Manifold & Solenoid Group.

259-8194 is part of the 233-7131 Parking Brake Manifold & Solenoid Group that is listed as a "Field Replacement for 208-5681" for machines of S/N ZSA01287-Up. So yes it will fit your machine. The coil specification at 25 ± 5 °C (77 ± 41 °F) is 8.8 ± 0.5 Ohms

jmchugh1958 said:

Incoming wire is 614-CN89 PU 18. I'm not sure how to tell where this originates, to trace the issue.

Click to expand...

You're on the wrong circuit. 614 in general (and there are literally dozens of them) is the power for the panel light lamps wherever they might be located. Look at any switch with an internal lamp and the power will come in to the lamp on a wire numbered 614-something Purple and go to ground via 200-some thing black.

Also if you look at Pages 10 & 11 of the schematic that I sent to you there is a schedule of “Wire Descriptions” that may help.

Thank You!! this is great info.

I had a similar problem on my old 287b ended up being the ecm ground under the floor board

Nige said:

Also if you look at Pages 10 & 11 of the schematic that I sent to you there is a schedule of “Wire Descriptions” that may help.

Click to expand...

Is there a possibility you'd send those to me as well?

bhoz93 said:

Is there a possibility you'd send those to me as well?

Click to expand...

Certainly, but in order to get the right one it requires the machine Serial Number.

Of course, sorry.

Build date of 5/6/05
SN: CAT0287BJ(ZSA01882)

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