Kohler M340 — Power to the System
Testing & diagnosis · Power supply board / logic board
For the Kohler M340, from the Kohler service manual.
Browse Kohler generators & specs →
Before you start
- When taking a voltage or resistance measurement at a ribbon cable pin, do not disconnect the ribbon cable from the board. Use a needle point probe.
Procedure
- Using a voltmeter, connect one test lead to TB-AC1-NA and the other to TB-AC1-NC. If the expected normal source voltage is not read, check the normal source and harness P1.
- Connect test leads to TB-AC1-NAS and TB-AC1-NCS. If approximately 19 volts AC is not read, check that the transformer is wired correctly.
- Connect test leads to TB-AC1-EA and TB-AC1-EC. If the expected emergency source voltage is not read, check the emergency source and harness P1.
- Connect test leads to TB-AC1-EAS and TB-AC1-ECS. If approximately 19 volts AC is not read, check that the transformer is wired correctly.
- Connect positive lead to TB-DC1-29 and negative lead to TB-DC1-34. Should read between 12 and 30 volts DC.
- Connect positive lead to TB-DC1-23 and negative lead to TB-DC1-34. Should read between approximately 12 and 30 volts DC.
- Connect positive lead to P2-13 and negative lead to TB-DC1-34. Should read approximately 10 volts DC.
- Connect positive lead to TB-DC1-30 and negative lead to TB-DC1-34. Should read approximately 10 volts DC.
- If the voltage readings were never correct, replace the power supply board.
Tools required
- voltmeter Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 19 VAC
- 12-30 VDC
- 10 VDC
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.