Help me here someone, sweltering heat here in GA and my blower has me very

Blower stopped working about a month ago, I put off dealing with it until now, why I don't know. <img border="0" alt="[ouch]" title="" src="graemlins/c.gif" />

Here is the story: <img border="0" alt="[typing]" title="" src="graemlins/yltype.gif" />

Fuse is ok, no power at the connector to the motor regardless of the switch position.

I found this procedure somewhere, might have been archives here

</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica"> Try the defroster. If the blower runs with the defroster, the blower motor is OK. </font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">Blower does not run.

</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica"> Try the blower on all speeds. If it runs on the highest speed, the problem is probably in the resistor pack, located in the fresh air plenum.

If the blower runs on the defroster, but not on the blower switch, you need a tester. The best type for this looks like an old-fashioned ice-pick with a clear handle and an attached wire.

Pull relay XXI, the blower relay, and check terminal 30 in the socket for 12 vdc. If there is power there, temporarily install a jumper between terminals 30 (Battery Bus) and 87 (load), then try the blower. If it now works, the problem is the relay. If not, the switch may be bad, or there may be a bad connection between the relay socket and the motor. </font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">When I jumper between 30 and 87, the blower works perfectly.

I changed relays (swapped the horn relay) and nothing. Works just fine with the jumper in, which is how I plan on running until I can figure it out

Is there something that triggers the relay that isn't obvious here? I'm really puzzled. <img border="0" alt="[soapbox]" title="" src="graemlins/soapbox.gif" />

 

If the blower does not run with either the defroster or a regular fan setting, and the relays are good (this is worth verifying - the double failure would be uncommon but maybe not impossible), the problem is probably in the control unit. The defroster and the fresh air fan run off of separate relays in our cars.

When 30 and 87 of the fresh air blower relay are jumped, the blower works perfectly because you are bypassing the control unit and supplying power directly to the speed selector switch and the resistor block.

When defrost is selected, there should be current between terminal J6 and ground; when any other setting is selected, there should be current between terminal J4 and ground. These are the inputs from the control unit to energize the relay coils for the defroster (XXII) and the fresh air blower (XXI) relays respectively.

If there's good current at #30 of both relays, the control unit is not energizing the relay - I would check the wiring to/from the control unit, the power supply to the control unit, and the control assembly, and failing that, the control unit/assembly would seem to have an internal problem.

And while you're at it, check the J plug at the bottom of the power panel to see if one or more of the wire connections have popped off their spade terminals - this has gotten me more than once.

Good luck.

 

James thanks for the information.

It turned out to be a disconnected arm on the slider in the control head.

Now for an R134a conversion and life will be good.