2000 Honda, A/c won't blow unless I bang up under the dash, both a/c lines are freezing under hood, no heat or a/c temps workin...

blower motor. or maybe wiring. to motor.

Agree, bad wire connection, or blower motor. The radiator is having its own issues, not related.

Banging up under the dash is un-jambing the blower motor and getting it to run. That means either the motor is shot and seizing up and needs to be replaced or something has fallen into the motor housing and keeps getting stuck preventing the motor from running until it gets knocked loose. Most likely the motor has begun to fail and needs to be replaced. As to the other symptoms you mentioned, I do not know enough about the HVAC systems to be certain, but I suspect that possibly the lines are freezing because the AC gets engaged when you put it on, but the blower motor doesn't run so the cold air sits in there instead of circulating and causes the system to freeze up.

Thanks for the info. I appreciate it. From what y'all say, sounds about right. Are blower motors hard to replace? I know where it is. I have taken out the glove box & loosened the dash before to get to the cabin filters, same process for the motor?

Another question... Since this issue, I have had to replace 2 radiators due to them cracking. Could it be related considering the extra pressure used by the blower motor trying to work and tention building up.. Any connection with the ac & radiator? Just curious. I replaced the thermostat and sealed the crack with jbwelding for a temp fix but my car is still running hot very soon after cranking. Do I need to replace water pump? Crazy, but since I added an at home can of a/c freon I started having problems that have continued to build up.

Just so you know, adding the AC refrigerant should have absolutely nothing to do with all the radiator problems. The radiator system only has to do with circulating water and antifreeze through the engine & the heater core & radiator, past the fans and the incoming air from driving, to lower the water temperature and keep the internal engine temperature down. The car is a 2000, so it is 16 years old now, so how many miles are on the engine? I ask, because your problem with the temperature gauge and radiator cracking sound more like a problem of severe overheating, and most likely are caused by a blown water pump or blown head gasket or blockage in the water system, especially since it starts overheating so soon after starting it. I would suspect a failed water pump first. As to the blower motor change, it appears to me that you SHOULD be able to unscrew the bottom of the blower motor housing and drop the motor out for replacement with out removing the entire blower motor assembly from the car as the manual shows, but with out seeing it I can't be sure. It does appear that you should be able to do it with a 1/4 in drive socket and some extensions and a swivel joint or two, but as I said I can't swear to it unless I actually looked at it.

The original answers I gave you about the blower motor change were based on the factory service manual available to the public, which can be long and drawn out and not always completely truthful. I have checked my Haynes manual for this vehicle, and according to that the blower motor can be changed without completely disassembling the dashboard just as I thought and mentioned to you. It also appears to be a fairly simple job. If you plan on keeping the car I would suggest you purchase a copy of the Haynes Manual for it. They really are an invaluable tool for most vehicles. Would like to know how you made out with your problems.