: AC Blower Relay

04-18-05, 02:14 PM
Okay well I was having a problem with the relay melting all the time and having to buy new ones. Someone on here told me to replace it with one that could take more power claiming that the factory ones couldn't handle it, so I did. It worked for a couple weeks, but now it seems to have blown as well. I haven't checked the fuses yet, but I will, and if the AC ones aren't blown I'm going to be pissed. I mean come on, why would the factory relay work for the 3 years that I've owned the car - and I'm sure a long time before that - if it wasn't up to the job? I've looked all over for bad wires and shorts and I haven't found any either. The next place I'm going to look is the control head, and I hope to God I don't have to buy another one of those.

04-18-05, 08:43 PM
I can't believe there's no one on here that doesn't know Cadillac HVAC systems really well that can help me.

04-19-05, 12:29 PM
Heeeeelp!!!!! This is like the most frustrating problem I've ever had with my car.

04-19-05, 09:47 PM
High current across the relay will cause it to melt - perhaps the blower motor is drawing too much current caused by a short, or dirty connections, or debris in the fan, or the bearing is seized...etc.

04-19-05, 10:35 PM
Nope, can't be the motor. I replaced the motor already and the problem still occurs. The blower resistors checked out fine, and I also got a new programmer right after the problem started. I've checked most of the wires and they look fine. The only thing it could be at this point I think is the control head, but it's only 2 years old. I'll check it when I get the chance, meanwhile, if anyone can think of anything else for me to check, let me know.

04-23-05, 11:11 PM
Okay well I did a sort of visual inspection of the control head and it looks fine. No metal that looks like it got hot and no melted plastic. The connectors all look nice and clean. Before a relay melts all the different settings do what they're supposed to do, except I don't get any air out of the top vents, so the upper actuator door must not be getting any vacuum.