Onan 5500 trouble code

[Carvin Marvin]

My onan 5500 is throwing a 27 code. "Connot sense voltage". Any suggestions as to what I can check prior to going to a onan repair place? Thanks in advance for any assistance. Marv

[Carvin Marvin]

My onan 5500 is throwing a 27 code. "Connot sense voltage". Any suggestions as to what I can check prior to going to a onan repair place? Thanks in advance for any assistance. Marv

[RV Wizard]

Carvin, welcome to iRV2.com. Your problem could be in any number of areas, You could have bad windings, slip rings, brushes, connections, wiring, or voltage regulator. You will need to start with a service manual and diagnose the problem. Recommend you start at the brushers and slip rings as this is the weakest link.

[wdbates]

Warranty on Onan genset is 3 yrs..1st year parts and labor. Parts only on remaining 2 yrs. On my onan 5500 gold we had same code and ended up replaceing the controler I dont know what year your motorhome is so I thought I would threw that in..Generator sounded like it wanted to start but had no B+ on voltage side of ing. As always clean and tighten all connections to B+ and grounds before heading to shop for repairs. I bought the manual for repair but soon discovered that most common breakdown was Controller.

[Carvin Marvin]

Thanks for the response. I pulled the brushes and could see no problem. The set is 6yrs old with 250 hours and the controller board was replaced 3 yrs ago. So I guess it's off to the Onan hospital. Marv