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1984 cat 943 electronic monitering sytem ?

fieldhopper ยท 2023-09-28 22:03

Does anyone have a breakdown of the red lights meaning? Have 1 that is on thats below the alternator light/lighting bolt. Didn't want to purchase manuals for it yet because not sure if keeping. Thanks

Replies5
  1. #1Nige2023-09-29 04:41

    Your thread said 943 so I'm assuming it's an early 3Y or 31Y machine. See attachment. If you decide to keep it you can download a manual for around $50 from Cat.

  2. #2fieldhopper2023-09-29 22:02

    This is a pic of the light that stays on when running. Serial number 04z00457. Its a early 943 no letter designation.

  3. #3Nige2023-09-30 06:49

    It might seem strange but the first possibility is dirty battery/ground connections. Also I suggest that you check the electrical connection on the back side of the EMS panel. That particular LED is not one of the four warning lights used in the 943 application. EDIT: While you are checking the electrical connections on the back side of the EMS panel see if there is a Part Number marked on it.

  4. #4fieldhopper2023-09-30 11:05

    I think I found the problem, the battery disconnect switch isn't killing the power. The previous owner has group 31 batteries in it and used those cheap junk bolt on cable ends, have to change out the ends with crimp on battery ends and double check the batteries but might be replacing them for the correct ones. Thanks for the help and info.

  5. #5Nige2023-09-30 13:19

    i think you're right. This is what I found ........ "Problems with light from the Light Emitting Diodes (LED's) in the panel of the Electronic Monitoring System (EMS) on the above models when the disconnect switch is OFF. This is not an indication of a problem in the Electronic Monitoring System. It is an indication of current leakage from the batteries, caused by dirt and moisture (water). The dirt and moisture on the batteries makes a ground connection which permits a very small flow of current. In effect this is functioning as a bypass circuit connected in parallel with the disconnect switch. Current leakage of this type can be a problem on any machine, and can discharge the batteries after a period of time. Because the LED's in the EMS panel need only a very small current to give light, they show a visual indication of the current leakage. On a machine without EMS, there is no indication of the leakage unless the batteries become discharged."