Kohler — PowerBoost IIIE Voltage Regulator Test Procedure
Testing & diagnosis
From a Kohler service manual covering: 4CFKM, 4CKM, 5CKM, 5CKM/SCKMR, ACKM/4CKMR. Check it applies to your exact model before use.
Applies to: Kohler 4CFKM, Kohler 4CKM, Kohler 5CKM, Kohler M18 engine, Kohler M20 engine
Before you start
- Hazardous voltage. High voltage is present at the heat sink of the voltage regulator. Do not touch.
Procedure
- Disconnect P10 connector from voltage regulator.
- Connect components per Figure 7-5.
- Turn variable transformer to zero and plug in.
- Increase to 100 volts; if lamp off, turn voltage pot clockwise.
- If lamp still off, regulator is defective and should be replaced.
- Increase to 120 volts; lamp should go out.
- Turn variable transformer to zero and unplug.
Tools required
- Variable transformer 0-140 volts Amazon
- 120-volt AC plug Amazon
- 120-volt 100-watt lamp Amazon
- AC voltmeter Amazon
- #14 AWG copper wire Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Lamp should go out at 120 volts
Full service-parts list: Kohler 4CFKM →, Kohler 4CKM →, Kohler 5CKM →
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.