mitsi puhz-rp4vha compressor not starting

[interstellafirm]

hi everyone, can anybody shed any light on my problem?
I've got a problem with a mitsubishi puhz-rp4vha single phase unit and the compressor won't start, i'm pulling my hair out with it.
I've put a new inverter board on, a new actm, and a new compressor. It had already had a new compressor and main pcb but never run and when I checked part number it didn't match what should be on the unit, maybe a 3 phased unit compressor had been installed. I put the new compressor on today and turned sw4 dip1 on to put in cooling test mode but all the compressor does is hum for a split second then cut out, checked it with inverter checker which was perfect, checked the feed was balanced which it was. the compressor is taking 6 amps on standby for compressor to heat up and when i start it, that drops off then gives a 6 amp burst but resets and tries again over and over, the compressor doesn't move at all.
I have checked the inverter board and everything seems fine other than i'm only getting 233vdc coming off the board going to the contactor but when it returns to the board after the actm it's reading a more positive 335vdc so a bit confusing there. i've checked the resistance from ac incoming to dc outgoing and all is fine resistance going one way only, and checked outgoing dc to u,v,w outgoing to compressor all ok.
contactor energises and i'm getting the same voltage on each side of the contactor so that seems ok, I can't think of anything else it can be and i'm running out of ideas can anybody think of something else that i've not checked? oh by the way it was coming up with fault code of under/over current when it was 1st diagnosed

many thanks colin

[install monkey]

crankcase heaters need to be energised for 12hrs-a lad changed 2 city multi compressors-returning them for warranty and they were deemed ok-just crankcase heaters wernt energised long enough

[interstellafirm]

i've changed loads of them and never had a prob starting them up straight away so not sure why this would be different?

[install monkey]

should the bus voltage on a power inverter be 580v dc on 1 phase units

[interstellafirm]

no mitsi say 335 on single phase 580 on 3 phase

[install monkey]

https://rapidshare.com/files/3957901...rp1.6-6vha.pdf;
service manual and parts list in the back
page 55 has some test procedures to diagnose

[stufus]

Make sure SW 5-1 is off
Cheers
Stu