blower no blow

[edsel]

ok 97 astro van. replaced resister to blower and blower still does not work. if i connect the power direct to the blower it works however going through the resister no go? did i get a second bad resister? any clues thanks, edsel...

[nxk2000]

Are you checking for power at the motor with a volt meter?
1. check for power and ground
2. the controls must send power in order for the resistor/relay to work. It also depends on how you run you jumper wire but with the system all hooked up the controls must work.

[Blue Bowtie]

The lower speeds are fused through "Heat-A/C" fuse, while the high speed blower is protected by a fusible link before the relay.

[edsel]

where is the fusible link before the relay located? i am connecting power directly from the battery to get the blower to work. i am not getting any power with the resistor connected. i am going to check the fuse and see if i can get power at the resistor and the blower.

[Blue Bowtie]

OOPS! My mistake. I have to eat my words. I just realized you have a '97, and it may have a 30A fuse in the UEC instead of a fuse link for the high blower.

[nxk2000]

Are you getting any voltage at the blower motor? This information would help to diagnose the problem. The only way the blower will get power is if the controls are working. Any speed. If you would like to check your fuses the high speed power comes from the a/c maxi fuse 30a under the hood and the lower speeds get there power from heater/ac fuse 20a inside the van.

The only way the blower motor would be completely inop is a bad wire/connection or if the controls are not working.

[edsel]

how do i check the control switch? the fuses check good but no juice is getting to the resistor.

[nxk2000]

I would check to make sure the controls are getting power at the connector for the controls. There should be an 8 pin connector with a brown wire that supplies the power. If that has B+ then look for a white wire. The white wire carries the B+ from the mode switch to the fan switch. Check the white wire from the back of the connector while it’s connected and you should have B+ anytime a mode is selected and with the ignition on. Of course if anything is bad you will be replacing the whole control unit. You can also check the output of the fan switch.

Yellow – low
Tan – medium low
Light blue – medium
Orange – high (power only goes to the relay in the resistor)

[dwv]

My 94 Astro had a similar problem. Blower motor and fuses were getting no power. When this occurred I also would get a "AntiLock Brakes" light on the dash.
This was caused by a flaky ignition switch, which the power to these components goes through. To workaround this until I replace the switch, I was able to manipulate the ignition lock cylinder after cranking to a position where these components would get power (the easiest indicator for me was that the AntiLock Brakes light went out. This workaround position for the ignition key was back toward the Off position.
Try manipulating your ignition key when cranked and see if power gets to your blower in some position.