Recently fitted a phone mount on handlebars which had a USB port to charge phone. Removed instrument panel from fuel tank and lifted fuel tank to route wiring to battery. Everything went fine until I turned on ignition to check everything worked OK. Lights came on reset the clock then started the bike and the low oil pressure warning light stayed on. It worked OK before I disconnected the instrument panel. Stripped the panel and fuel tank again checked plug connection and wiring but cannot find any fault. Anybody got an idea as to my next step. There is oil in the engine.