I've put the batteries in the battery compartment but the motor does not work

Check battery and connection.

Its faulty blower motor resistor. The low and medium speed on blower motor is controlled by resistor and its actual speed is high. So because resistor is not working, blower motors actual speed which is high is working.

It can be faulty blower motor or faulty blower motor resistor. Get the blower motor inspected. If it's faulty it has to be replaced.

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For blower motor testing and replacing, check the link below: ----

Blower motor Testing/replacing for all vehicles?

http://repairhelpcenter.blogspot.in/2012/02/blower-motor-replacing-for-all-vehicles.html

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These will help.

Thanks.

re move alt. have it re tested i had a signaler problem. tested fine at idle under load alt surged blow batt. also volt regulator may be constantly draining battery voltage regulator is inside alternator

Try a bigger battery or a battery charger.swap it to give enough power to start the engine. If that doesnt work than try checking the starter solenoid at your local auto store

Your 2005 Pontiac Sunfire battery group number is 75.

Check the Part Numbers of these batteries for your car - they all begin with "75."

Three batteries that fit your car are found at:
http://www.autozone.com/autozone/parts/2005-Pontiac-Sunfire/Battery/_/N-jmqtpZacy27

The "Group Number" refers to the dimensions of the battery - at battery that's too big wouldn't fit into
the battery compartment of the car.

Have you checked the wire from the alternator for continuity? A wire may look good but test bad.

HAVE BATTERY RECHARGED OR VECHICLE JUMP START.WITH VECHICLE RUNNING MAKE SURE ALTERNATOR IS CHARGING THE BATTERY.ALTERNATOR OUT PUT AT BATTERY SHOULD BE 13.5 - 14.5 VOLTS.IF NOT CHECK ALTERNATOR FUSE.CHECK ALTERNATOR + BATTERY FEED WIRE AND VOLTAGE REGULATOR WIRES MAKE SURE NONE OF WIRES LOOSE BROKEN OR DISCONNECTED.IF ALL IS GOOD AND ALTERNATOR OUT PUT LOW ALTERNATOR FAULTY.IF ALTERNATOR VOLTAGE OUT PUT OKAY. YOUR BATTERY DRAIN PROBLEM COULD BE FAULTY AC HEATER BLOWER MOTOR RELAY.CHECK INSIDE CAR WITH THE IGNITION SWITCH OFF.MAKE SURE RADIO TURN OFF.INTERIOR LIGHTS TURN OFF.HEAD LIGHTS TURN OFF.LISTEN FOR ANY NOISES LIKE BLOWER MOTOR RUNNING, OR FAULTY DOOR LOCK SOLENOID CLICKING NOISE.IF EVERY THING SO FAR OKAY.OTHER POSSIBLE CAUSES BATTERY DRAINING COULD BE FAULTY ALTERNATOR,FAULTY STARTER SOLENOID CONTACTS SHORTING OUT.THE PCM COULD DRAIN BATTERY IF FAULTY.THE NEW BATTERY COULD BE DEFECTIVE.

Series or paralell?. Should be parallel so you get 12 v0lts. two positives together and two negatives together

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