Hi, I'm new to the forum but not new to audio amplifiers, their design and repair...
I have a decent amount of experience with the CE4000, having done a half dozen of them for one client (output FETs, RF bypass caps, VIPer, burned traces, etc).
I have one on the bench (Ser#A107030) that exhibits a heavy current draw right after the inrush relay kicks in. I am running a BK variable isolation transformer with ammeter for troubleshooting. It will stutter a bit at 1.5-2A for about 200mS then pegs out at 6A and pops the slo-blow fuse in the iso-transformer if I let the amplifier remain in this condition.
I temporarily removed the PFC transistors and bypassed the PFC inductor with a wire jumper. The modulator would come up and phase relationship between H Bridge drive was OK. (I have Brownout override jumpers installed). Although rail voltage was decreased to ~+/-50V due to PFC bypass, the amplifier operated normally with low (<5mV) DC Offset appearing at the speaker terminals. The audio section seems to be in fine working order as does the SMPS (low voltage).
Following the service manual, I have connected an external power supply to the PFC controller and receive expected changes, however I cannot test it fully because the FETs are removed. All VIPer voltages are normal. I have also tried swapping PFC boost inductors with no change.
PFC gate drive looks good and PFC IXYS FETs test OK. I've temporarily replaced the primary filter caps which made no difference in symptoms.
Have their been instances where the transformer windings will break down at 400V but not 185V (PFC active vs inactive)?
Any clues where I can look next? I know the next answer will be "send it in", but I am confident that I can repair this. It's a challenge for me - you won't lose me, technically.
I guess I should add that I do not work at a "shop" and am not making any money from this.