Originally Posted by whittakerd
Can anyone help. My Onan gen. was working until I shut it down to fuel up. Now it only kicks over and then shuts off. The error code was 47. The Tank is full. The house batteries are brand new.
It appears fault code 47 is a magneto problem. You may want to call Onan for the nearest service center. Onan's number is 800-888-6626.
Here is the excerpt from the manual
IGNITION FAULT – FAULT CODE 47
WARNING Some genset service procedures present hazards that can result in severe personal injury
or death. Only trained and experienced persons with knowledge of fuels, electricity, and machinery
hazards should perform genset service. See Safety Precautions.
HGJAB, C – No ignition signal at P1–15 for 1 continuous second
HGJAA – No ignition signal at P1–5 for 1 continuous second
HGJAD, E, F prior to 2004 – No ignition signal at P1–5 for 1 continuous second
HGJAD, E, F after 2004 in Engine Run Only mode only – No ignition signal at P1–5 for continuous second
Wire connections, windings, ignition system, generator drive system
Diagnosis & Repair:
1. Verify that Last Fault is FC 47: Yes, continue diagnosis; No, troubleshoot actual last fault.
2. Alternating FC 47 and FC 37: Magneto gap too wide: reset magneto gap, retest.
3. Test Magnetos
A. Disconnect Connector P1.
B. Connect positive(+) meter lead to chassis ground.
C. HGJAA, D, E, F – Measure continuity to negative lead at pin P1–4 and P1–5: replace magnetos as
D. HGJAB, C – Measure continuity to negative lead at pin P1–15 and P1–20: replace magnetos as necessary.
4. HGJAD only – Run genset in Engine Run Only and externally excite field with 12 VDC or 24 VDC and
measure main and quadrature winding AC output.
5. Non EFI only – If the genset will not stay running measure genset frequency, quadrature winding and
main winding voltages using Break-Out Tool 420–0603 and Instruction Sheet R1098.
6. Measure AC frequency while changing engine rpm to determine if frequency response matches engine
rpm response: repair damaged generator drive system as necessary.
7. Measure field, quadrature and main winding resistance: clean slip rings, replace brushes, repair harness
and replace rotor or stator as necessary.
8. Measure field, quadrature and main winding resistance to ground: clean slip rings, replace brushes, repair
harness and replace rotor or stator as necessary.
9. Measure field, quadrature and main winding resistance to each other: clean slip rings, replace brushes,
repair harness and replace rotor or stator as necessary.
10. Check brush alignment per PSB-682a.
11. Verify that spark plug cables are secure on spark plugs: reconnect or replace as necessary.
12. Inspect ignition kill leads in harness and at connector P1: repair or replace lead, terminal or pins as necessary.
13. Measure spark plug gap: set gap or replace spark plugs as necessary.
14. Verify ignition spark condition.
15. Inspect spark plug lead, kill lead terminal at magneto and measure magneto air gap: replace terminals,
set gap or replace magnetos as necessary.
16. Dealers contact Distributor for technical support, Distributors contact factory for technical support.