Komatsu PC220LC-6 hydraulic pump wiring diagram needed

[Scottyk]

Aloha,
I recently bought a Komatsu PC220LC6 and finally got it running. Changed a lot of hoses cleaned out both fuel and hydraulic tanks and replaced all filters. While doing thes repairs I noticed that the wiring to the TVC solenoids on the front and rear pumps have had their connectors cut off and wires stripped and hand twisted together.

I have poor power when digging and a check with diagnostic display shows an E202 fault code for load sensing circuit.

Can anyone tell me the correct color coding for the TVC solenoid wiring I would like to make sure it is correct

 

[John C.]

What I have shows the wires for each both being white and black and the connectors being CO4 and CO13 if the numbers are still on the wires. Your code though shows short circuit in the LS select solenoid system. Resistance in that solenoid should be between 20 and 60 ohms.

What is the serial number of the machine?

 

[Scottyk]

I was wanting to make sure these wires were connected properly then try to figure out LS select solenoid.

My serial number is A80827 and I have white black red and yellow wires for some reason, is it possible that the black and white should be split to both and red and yellow is for LS select solenoid?

 

[John C.]

I had to get out a magnifying glass to look at the schematic to check the colors this time. I seem to remember the letters on the wires might be different than the actual color so I'll give you the letter. The drawing says the front pump TVC sensor wires are G which I understand to be green and B which I would think was blue but I seem to remember dimly that B might mean yellow in another language. The rear pump sensor shows W which I assume to mean white and R which I assume to be red.

The LS select solenoid valve is on the stack of solenoid valves with the small accumulator on one end. It is the second coil from the accumulator.

 

[Scottyk]

Ok I will check resistance on LS coil tomorrow. As far as the TVC I will see if I can find what kind of voltage each wire is producing and which end of solenoid to connect them to.

 

[Scottyk]

I found LS coil and it tested ok at 42 ohms. I have 25 volts and ground coming to it when key is on but I can't feel it or hear it click when energized.

As for the TVC solenoids, I found two wires with 25 volts and two with ground. I paired them up and tried all different combinations but I can't here or feel them working either. Even when I test each with a power probe I here no clicking or movement.

When key goes on I get an E02, when I go into diagnostic mode I get an E2:02 and and E2:31

Any further advice would be greatly appreciated

 

[Scottyk]

Here are codes showing up on panel. E02 shows up as soon as key goes on. The other two after I change panel to retrieve fault codes.

 

[John C.]

These valves don't click like you are expecting. The LS coil I believe will change when you change modes on the panel in the cab. It is what control the HO, SO, LO and FO modes. It should change when you shift between those modes. The TVC solenoids don't click at all.

The 202 codes says short in the LS select solenoid system and I don't show a 231 code. I think you probably have some wire worn through or shorting because oil has soaked the insulation and let them short. I don't think you are supposed to have 25 volts to either unit but I could be wrong. Ground wires on this series of machines usually go back to the computer which controls amperage flow through the coils.