I need a 2004 gran prix steering column wiring diagram so I can locate the ignition switch that controls the blower motor fan speed.

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The fan control switch is a thermostatic control, meaning the resistant range is now out of operating range youll need to replace that control

It could be a fuse. The fuse panel is located by the lower instrument panel just to the left of the steering column. There should be a diagram there telling you which fuse is to what as well. You may also want to check in the panel that is next to your battery. It usually has a cover on it that has a diagram as well

unless u are familiar with air bag assemblies I suggest u take it to a qualified mechanic..if u accidently touch something wrong u can deploy the bag and cause serious harm to yourself..u have to remove the air bag in the steering column

for the fan blower motor it could be the resistor or the fan control speed control switch is bad.for no lights replace the DRL RELAY for the lights. for the heated seats check the fuses.

inside the steering column locate the ignition remove wire to reveal screw to remove ignition that wire is what controls the buzzer and light itthe wire probrally wasnt in place correctly wich caused your problem

remove steering column covers and check connections at ignition switch..had a truck recently at dealership with similar problem and connector at back of ignition switch was melted..wires were for blower motor and battery feed to switch..had to replace switch and connector/pigtail

The blower speed controller is located under the hood on the right or passenger side on the heater housing just to the side of the heater hoses near the very back of the right cylinder head.
Yes that would cause the concern you are having.

there is no relay for the heater fan it's a 15 amp fuse and is on the accessories circuit. the reostat is responsible for all 3 speeds .with the key off there should be no voltage to the blower motor whether the fans speed fan switch is on or off. the fuse will be located in the fuse paneleither on the drivers left side in the dash or underneath the dash in the fuse block. you have a short in the harness that is under the dash and most likely it's a bad plug on the harness. your going to have to do some searching but that's where the problem short is... please rate

The blower motor speed control module is most likely shorted. This is very common on the gm w-body cars such as your grand prix.

Order and install a new blower motor speed control module and install. It is located in the hvac box, passenger side, near the blower motor.