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Home›Repair guides›Kohler›Controller Circuit Board Service Kits GM37440 and GM37441 Installation (Decision-Maker 340)

Kohler — Controller Circuit Board Service Kits GM37440 and GM37441 Installation (Decision-Maker 340)

Repair & overhaul

From a Kohler service manual covering: 125REOZJG, 150 REOZJ4, 150REZG, 175REOZT4, 2000REOZM, 2000REOZMD, 2250REOZDD, 275REOZJD, 275REOZJE, 400REZX, 400RZX, 48REOZK4…. Check it applies to your exact model before use.

Applies to: Kohler 125REOZJG, Kohler 150 REOZJ4, Kohler 150REZG, Kohler 175REOZT4, Kohler 2000REOZM, Kohler 2000REOZMD, Kohler 2250REOZDD, Kohler 275REOZJD, Kohler 275REOZJE, Kohler 400REZX, Kohler 400RZX, Kohler 48REOZK4

Before you start

  • Electrostatic discharge damages electronic circuit boards. Wear an approved grounding wrist strap.
  • Accidental starting can cause severe injury or death. Disconnect battery cables, negative lead first.

Procedure

  1. Acquire display data from Menu 6, Generator System and record all values.
  2. Remove the generator set from service; place master switch OFF, disconnect battery charger, disconnect starting battery negative lead first.
  3. Open the controller; remove cover and hardware, disassemble controller box if needed.
  4. Remove the controller circuit board external electrical connections; mark all disconnected leads with tape.
  5. Remove/replace the circuit board(s) from the controller observing circuit board grounding practices.
  6. Attach the controller circuit board(s) external electrical connections.
  7. Assemble the controller; swing front panel up, replace cover and hardware.
  8. Restore power to the generator set; reconnect battery negative lead last and battery charger.
  9. Set the programming mode via Menu 11, Programming Mode; enter access code (factory default 0).
  10. Verify the generator set system values in Menu 6, Generator System.
  11. Calibrate using Menu 9, Calibration; connect resistive load bank rated for standby rating.
  12. Enter Menu 3 Time and Date and Menu 10 Remote Control settings.
  13. Restore the generator set to service; move master switch to AUTO.

Tools required

  • Resistive load bank rated for generator set standby rating Amazon
  • RMS voltmeter and ammeter Amazon
  • TP-5829 Controller Operation Manual Amazon
  • Approved grounding wrist strap Amazon

Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.

Full service-parts list: Kohler 125REOZJG →, Kohler 150 REOZJ4 →, Kohler 175REOZT4 →, Kohler 2000REOZM →, Kohler 2000REOZMD →, Kohler 2250REOZDD →, Kohler 275REOZJD →, Kohler 275REOZJE →, Kohler 48REOZK4 →

Source: Kohler service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.

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