I this case the climate control is in the dash and a loose connection could be working with your slap.

Guys..Where is the blower motor? Inside or still firewall?

Okay, I understand that you have Automatic Climate Control. I know this is a basic question, but when you toggle the fan switch to increase blower speed, does blower speed increase to maximum with out the slam/bang on dash? Or it doesn't matter whether in auto control, or manual you have to slap the dash board. What Bill Boost says is definitely possible (loose connection on blower ckt.) It could also be a intermittent ground on the power side of the blower ckt. Also, turn the Auto Climate Control off by depressing the passenger, then the driver control. Then re-start Auto Climate Control in auto by adjusting the passenger control up to a temperature of 80*, see what happens with the blower. The blower motor can be accessed from under the dash passenger side. You first have to remove the right side sound insulator (hush panel), pull back the carpet, remove the IP compartment (glove box), remove Dash Integration Module from bracket. At this point hopefully you can see the blower motor and its power connector, check that connector for securely made up. The connector is three pin A,B,C. A=black, speed control (ground), B=purple, battery positive voltage, C=brown, blower motor flange ground. If you apply full potential (12 volts + to pin B, and bring pin A out to ground, you should see blower operate at maximum speed. Just a few thoughts here. Get back to us.

Hi Mark,
In auto or manual it is the same. The controller (via the LCD bar on the left side of the display) shows the blower speed increasing (either via a manual change or automatic) with no blower response at all. For the last two days, the slam/bang doesn't work anymore. I'm beating the crap out of my hand and getting nothing. I have repeatedly turned the control unit off (both passenger and driver'* side) and then turned on via auto by dialing in a 90degF temperaure (max). When the engine is cold, the auto won't ramp up the blower. Once the engine warms up, then the display shows a high blower speed (when in auto control) but the blower doesn't respond. When the engine is cold, I switch on the front defrost (in auto control) to try and get the blower to respond. The display shows the blower ramping up to high speed, but the blower doesn't respond.

I'm going to pull the motor and check the amperage into the motor with the control unit on. I don't believe the control unit is the problem. The bang/slam method worked mostly when I would bang on the right side of the dash or slam the passenger side door. A friend of mine just had the same problem with his wife'* caddie. The dealer said it was the blower motor (and accompanying electronics) and replaced the entire unit.

later,
Shawn

My parent'* 2001 has acted sporadicly- what you would expect of a loose connection. I believe it is the automatic climate control interface connection. When I say sporadic, I am referring to differing levels of functioning depending on the day.
I will remove a facia piece of plastic so I can access the CC and pop it out to inspect the connection.

Dan

Shawn, there is a speed signal input to the blower control module from the Instrument Panel Integration Module (IPM). The blower control module is located on the right side of blower. The blower control module provides DC logic to ramp the blower speed up or down as required. The speed changer portion of the blower ckt appears to be on the negative side (ground) of the blower. Also there is a 30 A fuse for the blower in the rear fuse block that you can check, although I doubt it is blown. I have no idea what input or signaling drives the fan speed indicator bars on the Auto. Climate Control LCD display.

We had erratic fan operation on 98 LeSabre with dual auto air. It was the circuit board that replaces the resistor pack on basis systems. The thing would operate at lower speed than expected; it would move up and down speeds. Sometimes it was barely running.

Whole job was over $100 part _ labor.

I'd check the electronic part before the mechanical blower. You can bypass the circuit board and apply direct (fused) power to the input on the blower to see if it operates correctly when it'* getting power. Then look at that variable power resistance board.

Check out the easiest fixes first.

Ok, I took out the sound insulator panel and took a look at the blower. I turned on the ignition and turn the Auto Climate Control to 90degF and the blower did not come on. I then adjusted the fan to full speed (manual) and the blower did not come on. Then, I took two fingers and "lightly" tapped on the blower housing and the fan started spinning up.

Now I believer it IS the blower motor, but what is wrong with it? It is making a noise when spinning. I recorded the sound and will upload it when I can get it off of my Clie'. It is very noticeable at the lowest blower setting. It sounds like the impeller is hitting something or the bearings are going bad.

Another interesting tidbit. I called the $tealership and they have two revisions on my 2002 bonneville. There is the first revision that is described as having a black motor housing without a "cooling tube" (part# 52495490). The second revision is listed as having a metallic motor housing and a "cooling tube" (part# 89018521). The $tealership wants $236.73 for the blower motor. I can order from www.gmpartsdirect.com for $118 (including */H).

So, here is my question. My current blower motor does NOT have a "cooling tube". Do I need to get the first revision part? Or am I suppose to buy the second revision part with the "cooling tube"? If GM discontinues a part because of a redesign, then they won't carry the old part anymore will they? I'm just wondering if the "cooling tube" is a heat pipe and the second revsision is a better design because the heat pipe is used to keep the motor housing (and motor) cooler. Something has killed mine after 3yrs of use (and 110k miles).

Your thoughts are appreciated. Right now I'm keeping the sound insulation panel off so I can get to the motor housing and "tap" it when it doesn't come on. I guess I'll be ordering from gmpartsdirect.

One other question, am I taking a chance on scewing something up if I don't pull my negative battery cable when I replace this blower? I don't have my radio code to reset the "Theftguard" on my OEM radio, so I'd like to do the blower swap without pulling the battery cable. Any worries? Hey, what do you do if you don't have your radio code for your radio when you lose power?

Again, thanks for your help.

Shawn
Silver_SE

I keep you posted,
Shawn

Shawn, It does sound like the blower motor bearings are worn creating too much drag against starting torque. You don't really have to disconnnect the battery if you don't wish to. The 2000+ Bonnevilles are different than prior years with respect to the theftlock on the radio. You may disconnect your battery without any ill effects to the radio. The radio reads the VIN when you reconnect power from the battery. The radio is encoded with your specific VIN, so if you removed the radio from your Bonnie & install it in mine then radio will not be operable because I have a different VIN.