HVAC blower doesn't work

Discuss your 2000-2005 Bonneville SE, SLE, SSEi, Buick Le Sabre 00-05 and Buick Park Avenue 97-05. Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.
Post Reply
mlkmgr
SLE Member
SLE Member
Posts: 33
Joined: Tue Aug 05, 2008 5:06 pm
Year and Trim: 01 Bonny SE

HVAC blower doesn't work

Post by mlkmgr »

01 SE with manual controls. the hvac blower will not work. i bought another motor from the yard and plugged in. no luck.
i double checked the 3 connectors i could see connected to the motor area and they looked good. the lights on the dash controls light up. not sure where to check next or what to troubleshoot.
anybody offer some insight??
imidazol97
Posts like an L67
Posts like an L67
Posts: 1204
Joined: Wed Jun 04, 2008 7:55 pm
Year and Trim: 2003 Lesabre Limited, 2008 Cobalt, 2014 Malibu

Re: HVAC blower doesn't work

Post by imidazol97 »

mlkmgr wrote:01 SE with manual controls. the hvac blower will not work. i bought another motor from the yard and plugged in. no luck.
i double checked the 3 connectors i could see connected to the motor area and they looked good. the lights on the dash controls light up. not sure where to check next or what to troubleshoot.
anybody offer some insight??
From my 2003 leSabre Helms service manual:

Fuse block rear seat #2 30A
Power to blower

Fuse block rear #37 10 A
to the control unit on

Have you check for power at the three prong connector to the blower?
A is a feedback wire
B should have 12 V when blower is on
C should be ground

I'd check these connecting to a good ground with your meter.
I suspect you'll find your problem in these checks.

The blower motor i run through a blower Motor Control Processor box. The ground wire goes to that box and the box shows a ground.
myfirstbonnie
Resident Gearhead
Resident Gearhead
Posts: 5530
Joined: Mon May 19, 2008 10:19 pm
Year and Trim: .
2015 Buick Enclave
2013 Buick Regal GS
Location: Hillsboro, Oregon

Re: HVAC blower doesn't work

Post by myfirstbonnie »

I am looking at a 2000 FSM and on the 3 prong connector to the blower motor:

pin A black wire speed control
pin B purple wire battery voltage
pin c brown wire blower motor flange ground


There is a blower control module mounted on the side of the AC housing that gets inputs from the HVAC controls for the blower. When the blower commanded on, check the voltage between pins A and B. It should vary between 4 to 6 volts when the fan speed commanded is changed.
mlkmgr
SLE Member
SLE Member
Posts: 33
Joined: Tue Aug 05, 2008 5:06 pm
Year and Trim: 01 Bonny SE

Re: HVAC blower doesn't work

Post by mlkmgr »

thanks for the replies. the car is in on a road trip at the moment. will check the voltages when the car returns.

i forgot all about the fuse block under the rear seat. perhaps it is something as simple as the fuse....i hope!!
myfirstbonnie
Resident Gearhead
Resident Gearhead
Posts: 5530
Joined: Mon May 19, 2008 10:19 pm
Year and Trim: .
2015 Buick Enclave
2013 Buick Regal GS
Location: Hillsboro, Oregon

Re: HVAC blower doesn't work

Post by myfirstbonnie »

Yes, I was assuming that was verified, but if the original motor went bad it probably took out the fuse.
Post Reply