5-speed manual. Why no power from the ignition to the motor?

• Black: Ground
• Blue/White: Power (12V) from HVAC control unit to blower relay
• Blue/Yellow: Power (12V) from blower relay to blower motor
• Blue/Black: Ground from blower motor to chassis

I know your trying to find power for your ignition or from your ignition What are you trying to do ?

This vehicle doesn't have a blower motor resistor ! It has a blower motor control module , if you have automatic climate control !
If manual climate control , then there is a blower motor resistor assembly !
Blower Motor Control Processor The blower motor control processor controls the speed of the blower motor by increasing or decreasing the voltage drop on the ground side of the blower motor. The HVAC control module provides a low side pulse width modulated signal to the blower motor control processor over the blower motor speed control circuit. As the requested blower speed increases, the HVAC control module increases the amount of time that the speed signal is modulated to ground. As the requested blower speed decreases, the HVAC control module decreases the amount of time that the signal is modulated to ground.
Air Speed - Front Control
The blower motor forces outside air into the vehicle's interior. The vehicle operator determines the blower motor's speed when the driver places the blower switch in one of 5 blower speeds. The blower motor will always operate in any switch position other than OFF, as long as the ignition switch is in the RUN position. The blower motor and mode switches are located within the HVAC control module. The blower motor OFF input is connected in series with the HVAC control module by the off blower motor control circuit.
Depending upon the selected speed, power is provided to the blower motor from either the ignition 3 voltage or battery positive voltage circuits from the fuse block. The battery positive voltage circuit only provides power when the High blower switch position is selected. Power and ground are provided to the HVAC control module by the ignition 3 voltage and the ground circuits.
Low Blower Speed When the Low 1 blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the low blower motor control circuit. Voltage is divided between 4 series resistors, a blower relay, and the blower motor to achieve the desired blower speed. The blower motor is grounded through the ground circuit.
Medium Blower Speeds When the Medium 1 blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the medium 1 blower motor control circuit. Voltage is divided between 3 series resistors, a blower relay, and the blower motor to achieve the desired blower speed. The blower motor is grounded through the ground circuit.
When the Medium 2 blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the medium 2 blower motor control circuit. Voltage is divided between 2 series resistors, a blower relay, and the blower motor to achieve the desired blower speed. The blower motor is grounded through the ground circuit.
When the Medium 3 blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the medium 3 blower motor control circuit. Voltage is divided between a series resistor, a blower relay, and the blower motor to achieve the desired blower speed. The blower motor is grounded through the ground circuit.
High Blower Speed When the High blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the high blower motor control circuit. The voltage energizes the blower relay, causing the blower motor to be connected directly to the battery positive voltage circuit. The blower motor and blower motor relay are grounded through the ground circuit.
Go on you tube an check out videos on trouble shooting blower motor circuit
Chevy Trailblazer EXT Blower Motor Won Turn Off

Ignition Timing 10 Degrees
Application:
With manual transmission

Note :
Before top dead center
*Warm idle speed 800 RPM
*Transmission in neutral (Parking brake engaged)
***CAUTION***
special procedures are required when making
adjustments
refer to service manual Ignition Timing 10 Degrees
Application:
With automatic transmission

Note :
Before top dead center
*Warm idle speed 750 RPM
*Transmission in drive (Parking brake engaged)
*All accessories off
***CAUTION***
special procedures are required when making
adjustments
refer to service manual.

Could be something in the key switch I suppose. There is a high speed relay for the blower that gets power directly from the battery, but the other speeds should go thru the fan switch and get power from the key switch.

Which of these systems does your vehicle have ?
HVAC Systems - Automatic
Blower Motor Control Processor
The blower motor control processor controls the speed of the blower motor by increasing or decreasing the voltage drop on the ground side of the blower motor. The HVAC control module provides a voltage signal to the blower motor control processor over the blower motor speed control circuit. As the requested blower speed increases, the HVAC control module increases the amount of time that the speed signal is modulated to ground. As the requested blower speed decreases, the HVAC control module decreases the amount of time that the signal is modulated to ground.

HVAC Systems - Manual
Air Speed - Front Control
The blower motor forces outside air into the vehicle's interior. The vehicle operator determines the blower motor's speed when the driver places the blower switch in one of 5 blower speeds. The blower motor will always operate in any switch position other than OFF, as long as the ignition switch is in the RUN position. The blower motor and mode switches are located within the HVAC control module. The blower motor OFF input is connected in series with the HVAC control module by the off blower motor control circuit.
Depending upon the selected speed, power is provided to the blower motor from either the ignition 3 voltage or battery positive voltage circuits from the fuse block. The battery positive voltage circuit only provides power when the High blower switch position is selected. Power and ground are provided to the HVAC control module by the ignition 3 voltage and the ground circuits.
Low Blower Speed
When the Low 1 blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the low blower motor control circuit. Voltage is divided between 4 series resistors, a blower relay, and the blower motor to achieve the desired blower speed. The blower motor is grounded through the ground circuit.
Medium Blower Speeds
When the Medium 1 blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the medium 1 blower motor control circuit. Voltage is divided between 3 series resistors, a blower relay, and the blower motor to achieve the desired blower speed. The blower motor is grounded through the ground circuit.
When the Medium 2 blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the medium 2 blower motor control circuit. Voltage is divided between 2 series resistors, a blower relay, and the blower motor to achieve the desired blower speed. The blower motor is grounded through the ground circuit.
When the Medium 3 blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the medium 3 blower motor control circuit. Voltage is divided between a series resistor, a blower relay, and the blower motor to achieve the desired blower speed. The blower motor is grounded through the ground circuit.
High Blower Speed
When the High blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the high blower motor control circuit. The voltage energizes the blower relay, causing the blower motor to be connected directly to the battery positive voltage circuit. The blower motor and blower motor relay are grounded through the ground circuit.

HVAC Control Module
The HVAC control module is a class 2 device that interfaces between the operator and the HVAC system to maintain air temperature and distribution settings. The battery positive voltage circuit provides power that the control module uses for keep alive memory (KAM). If the battery positive voltage circuit loses power, all HVAC DTCs and settings will be erased from KAM. The body control module (BCM), which is the vehicle mode master, provides a device on signal. The control module supports the following features:

If you mean that the Daytime Running Lamps (DRL) does not work when the blower motor does not work, then YES it COULD be an ignition switch problem. However, not very likely (please read on). The regular HIGH and LOW beam headlamps do not require the ignition switch to operate.

The main circuit that runs your regular headlamps also runs the blower motor HIGH speed. This has nothing to do with the ignition switch.
This circuit also operates the Power Mirror circuits and the Hazzard Flashers. You may want to check to see if these are also malfunctioning when this happens.

The Circuits for your other blower speeds go through the ignition switch along with the DRL control module, but your HIGH speed does not. So if it is your ignition switch, your HIGH speed should still work and your regular headlamps should still work. You will lose only your lower blower speeds and DRL if it is an ignition switch problem. You will have a bunch of other stuff going out if it is an ignition switch also. The ignition switch circuit that runs your DRL module also runs your Powertrain Control Module. So if it is an ignition switch problem causing your DRL to shut down, your engine will also be shutting down.

have you replaced the blower motor resistor yet,it is a printed circuit that has a floating ground.it is where the blower motor wires plug in to.if you unhook the motor wires and use your ground and hot wire on the motor it should test normal,

Three possible causes are the blower motor itself stalling (worn out bearings), the blower control module (intermittent internal problem or bad connectors/wiring) or the HVAC control (switch if manual, module problem if automatic). I would start by checking for power at the motor when not working.

Ignition switch is the culprit. On Fords for high speed blower motor is direct whereas the lower speeds go through the ignition switch. If there is an issue with the switch the blower will only work at high speed. A schematic will confirm that.