Phone wont boot - battery changed what should voltage be?

Hi

Iphone 4 was dropped in the bath.

Dried it out for 3 days in rice with the back cover off and battery out. Tried it after the 3 days but phone wouldnt turn on, it is not recognised in Itunes either.

I tested the voltage across pins 1 and 4 of battery and voltage was .9V. Battery was obviously fried so I replaced it with a new one. Phone will still not boot.

I took the battery out, connected USB cable to mains and tested the Voltage at the Battery connector (Pins 1 and 4). With the phone plugged in, and the battery out, the voltage across the two pins ( 1 and 4) was 2.2V where I would have thought it should be 5V?? Is this correct?

I am going to try a replacement dock connector and see if that works.

The water indicators inside the phone did not turn pick however the one on the dock connector and headphone jack did.

Have you any other suggestions and can you please confirm how you check if there is enough power going to the iphone?

Thanks