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Cat 308 right joystick issue

Swalemaker · 2026-03-29 18:41

New here, thank you for viewing. The thumb on my Cat 308CR is giving me trouble. Sometimes it works perfectly, sometimes not at all. At first I thought that it was heat related and then resetting overnight? Serial# GG802624 Code 4405-12 Help Please

Replies14
  1. #1Universal Parts2026-03-30 01:16

    Fault code 4405-12 typically indicates a fault in the engine cooling fan control circuit.

  2. #2Swalemaker2026-03-30 08:40

    Will check fuses. Thanks

  3. #3Swalemaker2026-03-30 09:18

    The only fan I see is belt driven? But all the fuses are good. Thanks

  4. #4Swalemaker2026-03-31 15:29

    Problem fixed.

  5. #5Nige2026-03-31 15:34

    Good to know. Would you care to elaborate a little on exactly what the cause was.?

  6. #6Swalemaker2026-03-31 15:40

    I tested voltage at the signal wire and found 2.8 volts with no change during wheel movement. A new joystick ($1,250 later) was the fix.

  7. #7Nige2026-03-31 15:54

    That’ll do it every time. I forgot those early models are a varying-voltage output signal compared to the PWM signals on today’s machines. Expensive fix though.

  8. #8Swalemaker2026-03-31 17:08

    It’s a 2020 Next Gen. I don’t know about the PWM part.

  9. #9Nige2026-03-31 17:33

    I’ll have to check with the electrical schematic but for a machine that recent I would have thought the sensor output would be PWM.

  10. #10Swalemaker2026-03-31 17:45

    I started testing on the percentage setting but couldn’t make it work. I was on pin #2 and #3. Pin #1 had 7.9 volts.

  11. #11Nige2026-03-31 19:14

    Now you have the replacement joystick installed would you mind testing for variations of voltage between Pins 2 & 3 as you roll the thumbwheel back and forth. This may help someone else in the future.

  12. #12Swalemaker2026-03-31 19:22

    For me, there is a certain amount of magic involved with electronics that work…I’m not touching it!

  13. #13jbernielh2026-04-02 15:22

    I'm with you... my 304C CR thumb had messed up doing strange things as well.. fortunately I have boom swing and it uses the same wheel switch on the LH joystick (only horizontal orientation) as the thumb on the RH.. plus same connectors.. I removed the left stick and plugged it into the right side and thumb was flawless.. finning wanted about 1200 USD for a new stick and I came across one on FB marketplace brand new in the box for 500 USD... guy had bought it to find out he had a broken wire somewhere else in the system and was stuck with it.. all back together and working like a charm and I ain't touching it now

  14. #14Swalemaker2026-04-02 15:46

    I thought of trying that, was pretty confident that I had a bad thumb switch. Glad you could find one for the discounted price.