Low airflow from a/c on high blower setting - 1995 GMC Sierra C1500

94 CHEVY Silverado ????,heat/ac fan not blowing. K1500?????? Hear clicking when selecting l'm, SET high but not blowing! WITH AIR OR NO A/C? FIRST IS FUSES, MAKE SURE THE BLOWER FUSE IS NOT BLOWN.
EASY NO? CHECK ALL FUSES FIRST. ON ALL ELECTRICS FAILING OF ANY KIND.
BAD FUSE, BAD WIRINIG , BAD CONNECTIONS. OR EVEN BAD RELAYS TO THE BLOWER OR BAD SWITCH BLOW.
THE OLD CARS , HAD A SPEED BLOW , RESISTOR BLOCK
THAT FAILS ON ALL SPEEDS BUT HIGH, SO ITS NOT THAT.
OWN A VOLT METER????
HERE IT IS, ANY OF THIS CAN FAIL THIS OLD
WE USES A VOLTMETER TO FIND THE POINT OF FAILURE.
A SHORTED BLOWER MOTOR CAN BLOW LEFT SIDE TOP
FUSABLE LINK.RIGHT FUSE BLOWN MAKES THE CONTROLLER DEAD.

Could also be clogged cabin air filter. Could have a blockage in the ducting, too.

Most likely the blower motor resistor or the fise for the low speeds. The high setting for the blower motor is on a separate circuit than the other lower settings.

Sounds like the blower resistor fuse link has popped.(not sure where the resistor is on a Beetle,but it is on the HVAC assembly somewhere-it requires airflow to keep the resistors cool).Most of the time the resistor overheats due to low airflow,if you replace the resistor,change the cabin air filter too.

Sounds like low speed coil in the Blower Fan resistor block has failed. The Blower Fan Resistor Block is usually located in the air ducting adjacent to the Blower Fan. The Resistor Block consists of 3 or 4 coils of special resistance wire attached to terminals which connect to the wiring that comes from the fan switch and then to the Blower Fan. The block is on the output side of the fan unit so that the airflow from the fan past the coils inside the duct assists in preventing them from overheating and burning out.
Access to the Resistor Block is from under the dash. To replace, remove the multi-pin connector and then undo the screws holding in the block. Check air duct for leaves and dirt which may have caused the coils to fail. .Replacement is the reverse procedure

the relay may be fine, it could be a resistor pack that is bad (if it's like what happened with my 2001 Cav [low and med1 did nothing, but med2 and high worked fine] there's a little modular board in the blower fan housing wedged at the front of the passenger side floor (waaaay up there) you'll probably have to pull the blower motor out to get to it, it's not a difficult thing to do yourself, but it's in an awkward position -- the cost (again if it's the same as for a 01) was ~$35+shipping online, and $65 from a local parts store (probably best to call to ensure prices)

2 airflow sensor out of operating range 3 coolant temp sensor out of operating range 4 oxy sensor indicates full rich 5 throttle potentiometer/airflow sensor... (low throttle pot signal with high airflow sensor signal) 6 throttle pot/airflow sensor...... (high throttle pot signal with low airflow sensor signal) 7 throttle pot...idle fuel adjustment failure(idle speed??) 8 intake air temp sensor...open or shorted circuit to sensor 11 Throttle pot at idle: Throttle pot idle trim out of normal range 12 Airflow meter: MAF signal out of range 14 Coolant thermistor: Resistance out of range or static during engine warm up 16 Air thermistor: Resistance out of range 17 Throttle pot: Out of range 18 Throttle pot/Airflow: Low throttle pot signal at high airflow 19 Throttle pot/Airflow: High throttle pot signal at low airflow 22 Fuel pump drive: ECU output to fuel pump relay 23 Fuel supply: Engine running too rich 24 Ignition Drive: ECU output to ignition Amp 26 Air leak: Engine running too lean 29 ECU self check 33 Injector Drive: ECU output to injectors 34 Injector: Looks for Injector dribble 37 EGR Drive: ECU output to EGR switching valve 39 EGR check sensor: EGR not working (normally pipe blocked) 44 Lambda (O2) sensor: Poor mixture control rich or weak (or misfire) 46 Idle speed Control valve: ECU output to Coil AB 47 Idle speed Control valve: ECU output to Coil CD 48 Idle Speed Control Valve: Stepper motor grossly out of position 66 Air pump: ECU output to air pump relay 68 Road speed sensor: Seen speed < 5km/h at high engine airflow 69 Drive/Neutral switch: Seen cranking in "D" or high airflow in "N" 89 Purge Valve drive: ECU output to purge valve
this is all I could find

The air doors are controlled by actuators that on of them or so may need replacing.

check to be sure that nothing has made a nest in your blower motor.. I have found mouse nests, rats nests, and even dead snakes inside the blower motor on these trucks..with all the extra weight inside the blower, the low speeds turn slow and will burn the resistor out quicker.

probably the vent in front of the blower motor lose, check that first.