will not crank on 2007 Isuzu i290 Pickup

starter good. ign switch good. will not crank. Relay does click when turn key to start. no power to starter solenoid.

Not enough info to help you. What model(assume it's an Hombre), engine 4 cylinder or V-6?
so sorry ... not my vehicle. I am fairly sure it's a V6. We know the starter is good .. jumped the solenoid with a wire and it turns over ... but not with the key. There is a 'click' that happens on one of the relays when we hit the Start position on ign. switch with clutch disengaged (so the clutch switch is good). I'm thinkin its the relay .. clicks .. but no conduction .. but the owner argues that. Also, he switched identical relays .. and it made no difference .. so I guess it's not a relay afterall. Oh ... and battery is good .. fairly new and well charged. Thank you very much for replying.