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Cat 623G where are the relays

gary nelson · 2023-10-27 04:13

No power to the air compressor clutch , found the fuses and breakers but relays ? have power to a/c switch and fan works thx

Replies11
  1. #1Nige2023-10-27 04:30

    How about a Serial Number to give us an idea. With that you are welcome to an electrical schematic. which shows the location of everything.

  2. #2gary nelson2023-10-27 04:32

    Fantastic!! Left work will get Monday morning and thank you

  3. #3gary nelson2023-10-27 05:18

    Need cab location of relays , which panel are they under

  4. #4Nige2023-10-27 05:41

    There are a dozen different models of 623G. Because I'm searching in the online system without a Serial Number it's like blundering around blinfolded in a dark room.

  5. #5gary nelson2023-10-29 17:43

    Hello nige Serial is ARW00358 Thx

  6. #6Nige2023-10-29 18:40

    Schematic on the way. Check your messages.

  7. #7gary nelson2023-10-29 19:10

    Thx I still can’t find relay box position There has to be a relay for a/c compressor

  8. #8Nige2023-10-29 19:51

    I had a quick look at the schematic and couldn’t see any relay for the a/c. I could be wrong though. Follow the circuit from the batteries to the fuse box, if the relay is there you have to find it.

  9. #9gary nelson2023-10-29 20:09

    yep no relay !!! As I’ve Just replaced compressor and it has no gas I thought maybe low pressure switch so i bridged it , still no good , I’m baffled

  10. #10Nige2023-10-30 05:25

    Well you have the schematic now. It should be easy enough to trace power/continuity to find the location in the circuit where the smoke is escaping.

  11. #11gary nelson2023-10-30 05:29

    Haha just home now , a/c switch on dash has 2 diodes on the switch that failed and hence no power to compressor clutch etc Therefore no need for relay Appreciate your input Thank you