AC Fan Buzzing
Thread Starter
Pro
Joined: Sep 2002
Posts: 688
Likes: 0
From: Rye Brook, NY
AC Fan Buzzing
I believe the AC fan motor is behind the center vents. There is a loud humming/buzzing sound when the fan is turned on. I think it gets louder with increased speed of the fan, but it is hard to tell for sure. Does anyone know what needs to be replaced? Is there a manual anywhere that I can look at? As long as the AC does not need to be discharged of refrigerant I could probably pull the dash off with instruction and try to fix it. Any ideas or suggestions would be greatly appreciated. Thanks.
Burning Brakes
Joined: Dec 2003
Posts: 1,066
Likes: 9
From: Eddy Texas
Your blower motor may have a problem , or it may just have some trash in the housing(leaves,etc). You can pull it out w/o removing your dash. It's under and behind your glove compartment. You can get to it by lying in a horribly unnatural position in your passenger footwell. I think you may to remove the glove box for access, not too hard.
C5 blowers often have trash in them from the "udders" on the firewall not being cleaned regularly, causing junk to get into the A/C housing.
C5 blowers often have trash in them from the "udders" on the firewall not being cleaned regularly, causing junk to get into the A/C housing.
Pro
Joined: Sep 2007
Posts: 735
Likes: 7
From: Bucks County Pa
Buzzing Noise in dash
Hi, I agree with streak, about the fan. Fan sounds are usually dirt, debris, or corroded bearings.
But you say the buzzing is behind the center vents, if that is true and not just the fan noise echoing from there, you have a different problem. It could be the control head oscillating because of a failing connection or component. Or a loose connection to it.
Instructions Below if you need to go in that direction.
Good Luck
==================================
HVAC Control Module Replacement
Removal Procedure
Remove the I/P accessory trim plate. Refer to Trim Plate Replacement - Instrument Panel (I/P) Accessory in Instrument Panel, Gages and Console.
++++++++++++++++++++++++++++++++++
Trim Plate Replacement - Instrument Panel (I/P) Accessory
Removal Procedure
Apply the parking brake for additional clearance around the parking brake lever.
Shift the transmission into SECOND (A/T), or FOURTH (M/T).
Remove the console. Refer to Console Replacement .
Grasp the shift control boot (M/T) and apply light pressure in toward the shift control lever, to begin to release the shift boot retaining tabs from the instrument panel (IP) accessory trim plate.
Using light pressure, continue to release the remaining boot retaining tabs, then lift the boot away from the trim plate.
Open the cigar lighter door and remove the ashtray.
Remove the IP accessory trim plate grille. Pry gently at the side edge with a flat-bladed screwdriver to release the tab.
Remove the accessory trim plate retaining screws next to the cigar lighter and behind the ashtray.
Remove the accessory trim plate retaining screw in the grille opening.
Grasp the sides of the accessory trim plate near the curve at the base.
Pull the trim plate rearward to release the locking tabs. Lift the rear of the trim plate to clear the driveline tunnel studs.
Disconnect the electrical connector from the cigar lighter.
Rotate the shift control boot (M/T) and reposition one end down into the shifter opening in the trim plate.
Lift the accessory trim plate over the shifter (and shift control boot, M/T), and remove the trim plate.
Installation Procedure
Lower the IP accessory trim plate over the shifter and under the parking brake lever. Position the shift control boot (M/T) as during removal and insert the boot up through the shifter opening in the accessory trim plate.
Connect the electrical connector to the cigar lighter.
Install the trim plate into position. Align the locator tabs and the locking tabs to the slots.
Begin to install the upper locator tabs and the upper locking tabs, then work downward to install the remaining tabs. Install the rear of the trim plate onto the driveline tunnel studs.
Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Install the accessory trim plate retaining screws. Tighten
Tighten the IP accessory trim plate retaining screw next to cigar lighter to 1.9 N·m (17 lb in).
Tighten the IP accessory trim plate retaining screw behind ashtray to 1.9 N·m (17 lb in).
Tighten the IP accessory trim plate retaining screw in grille opening to 1.9 N·m (17 lb in).
Install the accessory trim plate grille. Position the grille, then push to secure.
Install the ashtray.
Install the console. Refer to Console Replacement .
Align the shift control boot to the IP accessory trim plate opening, then press to lock the boot retaining tabs.
Adjust the shape of the boot for appearance, if necessary.
Shift the transmission into PARK (A/T), or REVERSE (M/T).
Release the parking brake.
+++++++++++++++++++++++++++++++++
Console Replacement
Removal Procedure
Remove the folding top stowage compartment lid extension panel (convertible). Refer to Compartment Lid Extension - Folding Top Stowage in Interior Trim.
Open the console door.
Pull up on the rear of the electronic traction control, ride control switch (2) in order to release the retaining clips; if the switch does not release from the trim plate, perform the following steps:
Carefully insert a screwdriver into the recess located at the rear of the switch.
Gently pull up the rear of the switch.
Disconnect the electrical connector (1) from the switch.
Disconnect the LED connector (1) from the wiring harness connector (2).
Remove the switch.
Using a small flat bladed screwdriver, carefully remove the console retaining nut covers.
Remove the nuts retaining the rear of the console.
Remove the nuts retaining the front of the console and the IP accessory trim plate.
Lift the rear of the console slightly and pull rearward to release the front of the console from under the IP accessory trim plate.
Disconnect the electrical connector from the electrical accessory plug.
Unscrew to remove the console electrical accessory plug retainer from the console electrical accessory plug housing.
Remove the electrical accessory plug housing from the console.
Disconnect the electrical connector from the fuel door release, rear lift window release (export) switch.
Remove the fuel door release, rear lift window release (export) switch from the console. Turn the console over and carefully insert a small flat bladed screwdriver to release the switch tabs.
Remove the console from the vehicle.
Installation Procedure
Install the fuel door release, rear lift window release (export) switch to the console. Align the switch, then push to secure.
Connect the electrical connector to the switch.
Install the electrical accessory plug housing to the console. Check that the cover plug is in place on the accessory plug housing.
Install the electrical accessory plug retainer onto the accessory plug housing. Screw the retainer onto the housing until secure.
Connect the electrical connector to the electrical accessory plug.
Important
Be sure to install the front of the console UNDER the rear of the IP accessory trim plate.
Install the console into position. Insert the front of the console under the rear of the IP accessory trim plate.
Loosely install the console retaining nuts.
Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Position the console to the IP accessory trim plate (at the front) and the floor extension carpet (at the rear) for best appearance. Tighten
Tighten the console retaining nuts to 10 N·m (89 lb in).
Connect the electrical connector (1) to the electronic traction control, ride control switch.
Connect the LED connector (1) to the wiring harness connector (2).
Insert the electronic traction control, ride control switch front retaining tab under the edge of the IP accessory trim plate.
Lower the rear of the switch into position, then push to secure the retaining clips.
Close the console door.
Install the folding top stowage compartment lid extension panel (convertible). Refer to Compartment Lid Extension - Folding Top Stowage in Interior Trim.
Remove the HVAC control module retaining screws.
Pull the HVAC control module out from the I/P center support bracket.
Disconnect the electrical connector from the HVAC control module.
Remove the HVAC control module from the vehicle.
Installation Procedure
Install the HVAC control module to the vehicle.
Important
The key should be in the off position when connecting the HVAC control module electrical connector to ensure proper calibration.
Connect the electrical connector to the HVAC control module.
Install the HVAC control module to the I/P center support bracket.
Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Install the HVAC control module retaining screws. Tighten
Tighten the screws to 1.9 N·m (17 lb in).
Install the I/P accessory trim plate. Refer to Trim Plate Replacement - Instrument Panel (I/P) Accessory in Instrument Panel, Gages and Console.
Important
Do not adjust any controls on the HVAC control module while the HVAC control module is self-calibrating. If interrupted, improper HVAC performance will result.
The engine must be running for proper calibration to occur.
Start and allow the engine to run for a least one minute.
But you say the buzzing is behind the center vents, if that is true and not just the fan noise echoing from there, you have a different problem. It could be the control head oscillating because of a failing connection or component. Or a loose connection to it.
Instructions Below if you need to go in that direction.
Good Luck
==================================
HVAC Control Module Replacement
Removal Procedure
Remove the I/P accessory trim plate. Refer to Trim Plate Replacement - Instrument Panel (I/P) Accessory in Instrument Panel, Gages and Console.
++++++++++++++++++++++++++++++++++
Trim Plate Replacement - Instrument Panel (I/P) Accessory
Removal Procedure
Apply the parking brake for additional clearance around the parking brake lever.
Shift the transmission into SECOND (A/T), or FOURTH (M/T).
Remove the console. Refer to Console Replacement .
Grasp the shift control boot (M/T) and apply light pressure in toward the shift control lever, to begin to release the shift boot retaining tabs from the instrument panel (IP) accessory trim plate.
Using light pressure, continue to release the remaining boot retaining tabs, then lift the boot away from the trim plate.
Open the cigar lighter door and remove the ashtray.
Remove the IP accessory trim plate grille. Pry gently at the side edge with a flat-bladed screwdriver to release the tab.
Remove the accessory trim plate retaining screws next to the cigar lighter and behind the ashtray.
Remove the accessory trim plate retaining screw in the grille opening.
Grasp the sides of the accessory trim plate near the curve at the base.
Pull the trim plate rearward to release the locking tabs. Lift the rear of the trim plate to clear the driveline tunnel studs.
Disconnect the electrical connector from the cigar lighter.
Rotate the shift control boot (M/T) and reposition one end down into the shifter opening in the trim plate.
Lift the accessory trim plate over the shifter (and shift control boot, M/T), and remove the trim plate.
Installation Procedure
Lower the IP accessory trim plate over the shifter and under the parking brake lever. Position the shift control boot (M/T) as during removal and insert the boot up through the shifter opening in the accessory trim plate.
Connect the electrical connector to the cigar lighter.
Install the trim plate into position. Align the locator tabs and the locking tabs to the slots.
Begin to install the upper locator tabs and the upper locking tabs, then work downward to install the remaining tabs. Install the rear of the trim plate onto the driveline tunnel studs.
Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Install the accessory trim plate retaining screws. Tighten
Tighten the IP accessory trim plate retaining screw next to cigar lighter to 1.9 N·m (17 lb in).
Tighten the IP accessory trim plate retaining screw behind ashtray to 1.9 N·m (17 lb in).
Tighten the IP accessory trim plate retaining screw in grille opening to 1.9 N·m (17 lb in).
Install the accessory trim plate grille. Position the grille, then push to secure.
Install the ashtray.
Install the console. Refer to Console Replacement .
Align the shift control boot to the IP accessory trim plate opening, then press to lock the boot retaining tabs.
Adjust the shape of the boot for appearance, if necessary.
Shift the transmission into PARK (A/T), or REVERSE (M/T).
Release the parking brake.
+++++++++++++++++++++++++++++++++
Console Replacement
Removal Procedure
Remove the folding top stowage compartment lid extension panel (convertible). Refer to Compartment Lid Extension - Folding Top Stowage in Interior Trim.
Open the console door.
Pull up on the rear of the electronic traction control, ride control switch (2) in order to release the retaining clips; if the switch does not release from the trim plate, perform the following steps:
Carefully insert a screwdriver into the recess located at the rear of the switch.
Gently pull up the rear of the switch.
Disconnect the electrical connector (1) from the switch.
Disconnect the LED connector (1) from the wiring harness connector (2).
Remove the switch.
Using a small flat bladed screwdriver, carefully remove the console retaining nut covers.
Remove the nuts retaining the rear of the console.
Remove the nuts retaining the front of the console and the IP accessory trim plate.
Lift the rear of the console slightly and pull rearward to release the front of the console from under the IP accessory trim plate.
Disconnect the electrical connector from the electrical accessory plug.
Unscrew to remove the console electrical accessory plug retainer from the console electrical accessory plug housing.
Remove the electrical accessory plug housing from the console.
Disconnect the electrical connector from the fuel door release, rear lift window release (export) switch.
Remove the fuel door release, rear lift window release (export) switch from the console. Turn the console over and carefully insert a small flat bladed screwdriver to release the switch tabs.
Remove the console from the vehicle.
Installation Procedure
Install the fuel door release, rear lift window release (export) switch to the console. Align the switch, then push to secure.
Connect the electrical connector to the switch.
Install the electrical accessory plug housing to the console. Check that the cover plug is in place on the accessory plug housing.
Install the electrical accessory plug retainer onto the accessory plug housing. Screw the retainer onto the housing until secure.
Connect the electrical connector to the electrical accessory plug.
Important
Be sure to install the front of the console UNDER the rear of the IP accessory trim plate.
Install the console into position. Insert the front of the console under the rear of the IP accessory trim plate.
Loosely install the console retaining nuts.
Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Position the console to the IP accessory trim plate (at the front) and the floor extension carpet (at the rear) for best appearance. Tighten
Tighten the console retaining nuts to 10 N·m (89 lb in).
Connect the electrical connector (1) to the electronic traction control, ride control switch.
Connect the LED connector (1) to the wiring harness connector (2).
Insert the electronic traction control, ride control switch front retaining tab under the edge of the IP accessory trim plate.
Lower the rear of the switch into position, then push to secure the retaining clips.
Close the console door.
Install the folding top stowage compartment lid extension panel (convertible). Refer to Compartment Lid Extension - Folding Top Stowage in Interior Trim.
Remove the HVAC control module retaining screws.
Pull the HVAC control module out from the I/P center support bracket.
Disconnect the electrical connector from the HVAC control module.
Remove the HVAC control module from the vehicle.
Installation Procedure
Install the HVAC control module to the vehicle.
Important
The key should be in the off position when connecting the HVAC control module electrical connector to ensure proper calibration.
Connect the electrical connector to the HVAC control module.
Install the HVAC control module to the I/P center support bracket.
Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Install the HVAC control module retaining screws. Tighten
Tighten the screws to 1.9 N·m (17 lb in).
Install the I/P accessory trim plate. Refer to Trim Plate Replacement - Instrument Panel (I/P) Accessory in Instrument Panel, Gages and Console.
Important
Do not adjust any controls on the HVAC control module while the HVAC control module is self-calibrating. If interrupted, improper HVAC performance will result.
The engine must be running for proper calibration to occur.
Start and allow the engine to run for a least one minute.
Drifting
Joined: May 2000
Posts: 1,917
Likes: 3
From: Southern NH
My fan has always been noisier with the heat on vs. AC and I assumed it was due to the way air flows over the temp mix doors (dual zone). It doesn't affect the performance of the HVAC but I'll agree it's annoying.
Thread Starter
Pro
Joined: Sep 2002
Posts: 688
Likes: 0
From: Rye Brook, NY
I took the panel off in the passenger footwell. The motor is definitely the culprit and is making a loud noise that can even be heard outside the car with the negine off and the ignition on.
How do I remove the motor? Does anyone have a diagram or instructions? It looks fairly easy. Any idea of the cost for a replacement blower? Thanks everyone for the help. Adam
How do I remove the motor? Does anyone have a diagram or instructions? It looks fairly easy. Any idea of the cost for a replacement blower? Thanks everyone for the help. Adam
Your blower motor may have a problem , or it may just have some trash in the housing(leaves,etc). You can pull it out w/o removing your dash. It's under and behind your glove compartment. You can get to it by lying in a horribly unnatural position in your passenger footwell. I think you may to remove the glove box for access, not too hard.
C5 blowers often have trash in them from the "udders" on the firewall not being cleaned regularly, causing junk to get into the A/C housing.
C5 blowers often have trash in them from the "udders" on the firewall not being cleaned regularly, causing junk to get into the A/C housing.
Pro
Joined: Sep 2007
Posts: 735
Likes: 7
From: Bucks County Pa
AC Blower Removal
Hi, You may want to try vacuuming out any dirt or debris, and putting a bit of high temp grease on the bearings, before you replace it, or even checking the tightness of the mounting screws, that has worked for others.
SEE BELOW
Good Luck
++++++++++++++++++++++++++++++++++
Blower Motor and Fan Replacement
Removal Procedure
Caution
Unplug the blower motor before removal. Blower motor case contact with any ground may start the fan and cause personal injury.
Caution
Before servicing any electrical component, the ignition key must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures. If a tool or equipment could easily come in contact with a live exposed electrical terminal, also disconnect the negative battery cable. Failure to follow these precautions may cause personal injury and/or damage to the vehicle or its components.
Disconnect the negative battery cable.
Remove the I/P lower insulator panel - RH. Refer to Closeout/Insulator Panel Replacement - Instrument Panel (I/P) Lower in Instrument Panel, Gauges and Console.
====================================
Closeout/Insulator Panel Replacement - Instrument Panel (I/P) Lower RH
Removal Procedure
Using a flat bladed tool, carefully pry the I/P courtesy lamp assembly from the RH lower closeout panel.
Remove the RH lower closeout panel push-in retainers from the I/P lower support beam.
Lower the closeout panel slightly, and finesse the left side of the closeout panel from above the driveline tunnel.
Insert the I/P courtesy lamp assembly up through the opening in the closeout panel.
Continue to lower the closeout panel, then pull to remove from the dash panel studs.
Remove the closeout panel.
Installation Procedure
Install the RH closeout panel onto the dash panel studs.
Insert the I/P courtesy lamp down through the opening in the closeout panel.
Raise the closeout panel slightly, and finesse the left side of the closeout panel into position above the driveline tunnel.
Install the closeout panel push-in retainers to the I/P lower support beam.
Align the I/P courtesy lamp to the closeout panel opening, then push to secure.
======================================
Disconnect the blower motor control module electrical connector from the blower motor.
Disconnect the blower motor cooling tube from the HVAC module.
Remove the three blower motor retaining screws.
Remove the blower motor with fan from the HVAC module.
Installation Procedure
Install the blower motor with fan to the HVAC module.
Install the blower motor retaining screws. Tighten
Tighten the blower motor retaining screws to 1.7 N·m (15 lb in).
Connect the blower motor cooling tube to the HVAC module.
Connect the blower motor control module electrical connector to the blower motor.
Install the I/P lower insulator panel - RH. Refer to Closeout/Insulator Panel Replacement - Instrument Panel (I/P) Lower in Instrument Panel, Gauges and Console.
Connect the negative battery cable. Tighten
Tighten the negative battery cable bolt to 15 N·m (11 lb ft).
Program the transmitters. Refer to Transmitter Programming/Synchronization in Keyless Entry.
++++++++++++++++++++++++++++++++++++++
SEE BELOW
Good Luck
++++++++++++++++++++++++++++++++++
Blower Motor and Fan Replacement
Removal Procedure
Caution
Unplug the blower motor before removal. Blower motor case contact with any ground may start the fan and cause personal injury.
Caution
Before servicing any electrical component, the ignition key must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures. If a tool or equipment could easily come in contact with a live exposed electrical terminal, also disconnect the negative battery cable. Failure to follow these precautions may cause personal injury and/or damage to the vehicle or its components.
Disconnect the negative battery cable.
Remove the I/P lower insulator panel - RH. Refer to Closeout/Insulator Panel Replacement - Instrument Panel (I/P) Lower in Instrument Panel, Gauges and Console.
====================================
Closeout/Insulator Panel Replacement - Instrument Panel (I/P) Lower RH
Removal Procedure
Using a flat bladed tool, carefully pry the I/P courtesy lamp assembly from the RH lower closeout panel.
Remove the RH lower closeout panel push-in retainers from the I/P lower support beam.
Lower the closeout panel slightly, and finesse the left side of the closeout panel from above the driveline tunnel.
Insert the I/P courtesy lamp assembly up through the opening in the closeout panel.
Continue to lower the closeout panel, then pull to remove from the dash panel studs.
Remove the closeout panel.
Installation Procedure
Install the RH closeout panel onto the dash panel studs.
Insert the I/P courtesy lamp down through the opening in the closeout panel.
Raise the closeout panel slightly, and finesse the left side of the closeout panel into position above the driveline tunnel.
Install the closeout panel push-in retainers to the I/P lower support beam.
Align the I/P courtesy lamp to the closeout panel opening, then push to secure.
======================================
Disconnect the blower motor control module electrical connector from the blower motor.
Disconnect the blower motor cooling tube from the HVAC module.
Remove the three blower motor retaining screws.
Remove the blower motor with fan from the HVAC module.
Installation Procedure
Install the blower motor with fan to the HVAC module.
Install the blower motor retaining screws. Tighten
Tighten the blower motor retaining screws to 1.7 N·m (15 lb in).
Connect the blower motor cooling tube to the HVAC module.
Connect the blower motor control module electrical connector to the blower motor.
Install the I/P lower insulator panel - RH. Refer to Closeout/Insulator Panel Replacement - Instrument Panel (I/P) Lower in Instrument Panel, Gauges and Console.
Connect the negative battery cable. Tighten
Tighten the negative battery cable bolt to 15 N·m (11 lb ft).
Program the transmitters. Refer to Transmitter Programming/Synchronization in Keyless Entry.
++++++++++++++++++++++++++++++++++++++
Last edited by bestvettever; Sep 10, 2008 at 11:22 PM.
Melting Slicks
Joined: Jul 2007
Posts: 2,939
Likes: 7
From: Simpsonville SC
St. Jude Donor '09-'10
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