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Caterpillar th330b Problem with hydraulic and electrical controls

Baltoi Ionut ยท 2021-07-26 15:41

Good evening, I'm new on this forum and I'm from Romania, I don't know if you've heard of this country before, that's why please forgive my grammatical mistakes. I have a Caterpillar Th330B telescope, which has the following problem, its arm remained raised and no longer makes any command, and the exclamation mark light is on board. Not having a service nearby, I took all the electrical installation to check it, I found some more gnawed cables, I repaired them, and I came across the following problem, the valves (PSH) from the rear distributor, they do not have current, they come only on one negative current cable always and on two positive current always, on the rest nothing. I haven't gotten the error codes yet but I will try to diagnose it using the key twist method 3 times in contact to display them, has anyone encountered such a problem, could you help me, would the computer be faulty? The chassis series is as follows: CATTH330PSLB01951

Replies18
  1. #1Txhayseed2021-07-26 17:51

    If you had something snacking on your wiring I would check and double check first. Make sure what you fixed is correct. I have been known to. Cross a wire of two over the years mending harnesses. It happens so i would check that. Since you know you do have some electrical issues I would go point to point checking the harness. By that I mean unplug the coils and then go to the controller plug that feeds the coils and ohm out each wire and make sure you have continuity throughout the harness. Im guessing you already checked fuses etc. Since it was ate through it could have grounded out. I would really give my electrical a second look and make sure that's sorted first. I would really lean more towards that then the controller itself. They do fail but from experience its usually something electrical causing the issue. I would get the schematic and do you due diligence first then move on from there. I guess I should ask it was working fine before it became a buffet for a rodent ??

  2. #2Baltoi Ionut2021-07-27 03:04

    It worked well, but for a while it was on for 5 minutes, it warmed up, the arm was locked and after it cooled down, it worked a little, so I checked all the wires in the cabin, it was really some cables eaten but only the plastic on them. The only cable that was broken by the mice in the cabin was a minus one that was divided into several and I tied it again. I tend to think it was the computer because on the chassis of the machine the previous owner welded and there are welds, and I'm afraid it didn't burn.

  3. #3Baltoi Ionut2021-07-27 05:14

    As an error code it looks like I have it active, but I don't know where the solenoid is for this code where does anyone know? A039088205

  4. #4Txhayseed2021-07-27 08:40

    All the solenoids will be at the main function manifold. Rear of machine under the boom pivot. The solenoids are covered by plastic covers. You have to remove the 4 corner screws to gain access to the solenoids.

  5. #5Nige2021-07-27 11:05

    Here is the troubleshooting procedure for the Code. However it appears as though the wire numbers in the procedure do not correspond with the ones that are in the electrical schematic. The electrical schjematic shows a switch, the procedure shows those wires operating a solenoid valve.

  6. #6Fransman2022-02-06 07:41

    Good afternoon everyone, I'm new on this forum and I'm also having problems with the hydraulic boom controls of my Caterpillar th330B. In order to locate the problem, can you give me the procedure to display the error codes on the dashboard. Last month, I replaced the starter because it was dead. But when I put it back together I placed a ground terminal on a positive connection. When I switched on the ignition I immediately noticed that the electric fuel pump was not working so I knew I had made a mistake. So I rewired everything correctly and the machine started. But from that moment the hydraulic functions of the mast no longer worked and an alarm remained continuously on the dashboard. I checked all the cables and the fuses, everything seems to be in order. I think the problem is either the mast main solenoid or the ECM. That's why I'm looking for how to display error codes on the dashboard. Thanks for your help, and have a nice day

  7. #7Nige2022-02-06 11:16

    Attached is the procedure for using the machine Monitor Panel to display the full list of Diagnostic Codes. When you do the procedure make note of those Codes that are Active. A letter "A" will appear in the LH display window when a Code is Active.

  8. #8Fransman2022-02-07 15:00

    thanks for the procedure, it's a little bit more tricky than on the paper but it work. here is the active codes: A039113805 A039224105 A039224205 A039228205 A039218105 it look like a lot... Can you explain me the meaning of these? thanks a lot

  9. #9Nige2022-02-07 16:59

    Well for a start they all end in 05 so the fault is the same for all of them - FMI05 or "current below normal". This is usually an open circuit somewhere. CID1138 - Boom Cylinder Rod Retract Solenoid CID2241 - Tilt Cylinder Retract Solenoid CID2242 - Loader Auxiliary Valve Solenoid #1 CID2282 - Boom Telescope Cylinder Retract Solenoid CID2181 does not exist. Are you sure it's not CID2281.? See attachment for the troubleshooting procedures. I'll send you an electrical schematic. You'll probably need it.

  10. #10Fransman2022-02-08 04:55

    you are right it's CID2281. I will do the troubleshooting procedure. I'm agree with you with the open circuit, I will check again all the fuse and relays to be sure. thanks if you can send me an electrical schematic, it will be helpful. have a nice day,

  11. #11Nige2022-02-08 06:47

    I sent it already. It will be in your message inbox. Look for the envelope icon in the top RH corner of the main forum page.

  12. #12Nige2022-02-08 09:45

    I have not studied the electrical schematic in detail but from a brief look the common possibilities between the five troubleshooting procedures is a lack of power on wire 133-OR (shorted to ground or cut) or a poor ground connection. You could start there first.

  13. #13Fransman2022-02-08 13:58

    Hi Nige, after hours of investigation (everything was ok with cabling and plug) I have find the issue. It was the electronic track between the head of the PHS valve and inner components that was partially cut (1 track) I have repair the track, and now, everything is working thanks for your help, this forum is great, without it I would never find so fast.

  14. #14MattNam2023-01-24 05:16

    Hi Nige, Trust you are well. Could you help me with troubleshooting the Active error codes on a CAT TH340B? A 039 1845 05 A 039 1846 05 Looking forward to your reply. Regards, Matthias

  15. #15Baltoi Ionut2023-01-24 07:02
  16. #16Baltoi Ionut2023-01-24 07:03
  17. #17Baltoi Ionut2023-01-24 07:04

    Here are the meanings of your error codes and diagnostic methods

  18. #18MattNam2023-01-26 01:16

    Thank you very much!