A/C problems
 

Having problems with my A/C. Bare with me as I try to explain the problem. The compressor comes on and the air is cold. The problem is when I turn the fan speed knob (most of the time) nothing happens. In the beginning if I turned the setting to 4 and hit the dash just right or hit a bump in the road, it would start blowing. Now hitting the dash is not working at all and hitting a bump only helps sometimes. Any suggestions?

Replace blower/blower motor.
Remove the glovebox to access it.
Easy job, common issue.

^close, but it's actually the resistor, not the motor.

Search for blower motor resistor.

See this too:

:scratch: Same issue on 2x Maximas and it was the blower.
The resistor issue is when it only works on speed 3-4 on manual climate controls..yes?

When you hit bumps and it turns on or hit and and it turns on its a failing motor in my personal experience.

Edit: OP when it turns on 4 after a bump or hit, can you then turn down the fan speed and keep it running?..

On a manual control system, speeds 1 - 3 go through the blower motor resistor. Speed # 4 of the fan switch is a direct connection to the fan motor, bypassing the blower motor resistor.

The fact that the op has problems regardless of the fan switch position makes me think that the blower motor resistor is OK.

The blower motor could be the problem, but I also question the speed select switch. It is close to a 50-50 thing, but I lean a little more towards the switch itself.

To me, this is a tough call without hands on.

i had the blower resistor go on me. The blower motor still worked on setting #4. All the other settings were shot.

It sounds like a connection is loose/needs to be resoldered.

When it only worked on high that makes me think the resistor is bad. But the bumping says the brushes in the blower motor might be worn down.

I'd start by checking for voltage at the power wire on the blower. Use a test light or a multimeter, each can be had for under $10 and are very useful for diagnostics if you know how to use them.