Service Manual

Table Of Contents
7. Troubleshooting 10-2019
160 A062J683 (Issue 1)Copyright © 2019 Cummins Inc.
ii. Verify that the magnet that is in the flywheel is still magnetic, is not
damaged, and/or has not been misplaced. Replace the flywheel if
necessary.
iii. If the magneto coil is still not functioning properly, replace it.
d. Inspect the spark plugs for damage and proper gap:
Remove and inspect spark plugs. If they are damaged or dirty, replace
them.
Measure the spark plug gap. Re-gap if necessary.
Code 27 - Voltage Sense Lost
Logic: The generator set frequency is greater than 40 Hz and voltage sensed is
less than 5 VAC on one or both lines. (The control senses if one line is lost or
disconnected.)
Possible Causes:
Generator set loads
Alternator windings
Wire connections
Diagnosis & Repair:
1. Check the last fault recorded.
If this fault has not been repaired, troubleshoot that fault.
2. Measure the AC voltage.
3. Disconnect the generator set control P1 connector.
4. Verify that the P1 and P2 pin sockets are fully inserted and inspect the pin
socket condition for corrosion and acceptable condition of contact wipers. To
check contact wipers, use one of the devices below:
A mating pin connector
A pin gauge the same size as the mating control connector pin (0.045 in)
Any suitable device that will not damage the inside contact wipers of the
pin socket
If necessary:
Clean, repair or replace any pin sockets.
Fully insert any partially inserted pin sockets.
5. Inspect the condition of P1 and P2 pins on the control board. If they are
damaged or severely corroded, clean or repair if possible, or replace the control
board.
6. When reconnecting the harness plug to the connector, ensure that the pair are
fully seated next to each other.
7. Reconnect the P1 connector and test-run the generator set for fault occurrence.