MIL light and bleeper won't reset

[fatjon]

I usually run on an Emerald ECU but while waiting for word on why the air con won't work on the Emerald I want to go back to the MBE. It has a problem and is putting up a MIL light and beeping at me as soon as I turn on the ignition. I made up a lead and connected to it with the diags and cleared stored codes but the beeper and MIL light persist. They don't go and then come back when I start the engine just never clear at all. The engine runs fine on the Emerald but as rough as hell on the MBE. Is there some way to interogate it and see what exactly it thinks is wrong. I couldn't see any obvious way of finding out, only a way of resetting the codes. The throttle pots are new and both showing about 14.8% b ut it runs so roughly that seeing if the lambdas are reading correctly is difficult due to the misfiring.