how to replace heater control module in 98 24 V
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Joined: May 2003
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From: Salt Lake City, UT
how to replace heater control module in 98 24 V
My truck ONLY blows out the defrost vents. It is winter,.. (so I don't know when it started,..I leave it on defrost in winter because that's what matters). I went to switch it on vent or ac to blow out the front vents, but nothing happenned. I tried all other setting but it just stays on defrost. My first thought was the vacuum line, (I just changed my fuel filter 2 weeks ago) it was loose, so I checked (it had vacuum) and plugged it back in. Hoping that would fix it. But nothing changed. I don't know anything else to check other than to remove the heater control and replace it (or at least check it out). I have NO IDEA how to pull it out, but I suspect I might have to remove the dash, which sucks. Anybody who knows, will you please chime in if you have any direction? I love this truck but like to keep everything functioning.
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Joined: May 2003
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From: Salt Lake City, UT
OK, I got the front of the dash off, it was easy,. and I have done it before but I'll bet it was 25 years ago. I cannot feel vacuum at the little black vacuum hose (which is the hose thatcomes from the vacuum pump (I hope). It is so small,..I am not even sure if I "should" feel the vacuum by putting my finger on it. I can sure feel the vaccum up in the engine bay when I put my finger over the end of the larger vacuum hose. Anybody know if I SHOULD be able to feel the vacuum with my pinky,..or do I need to find another way to test.
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Joined: May 2006
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From: Pacific NW, B'ham, Kalispell MT
Is it your blend door actuator you are fiddling with?
My heater acted out years back and it was the splitter at the firewall. It was cracked and allowing loss of vacuum enough to not allow the selector to operate the blend door..... You can find stainless steel parts in the fish section at pet stores that will replace the plastic one FYI....
Kurt
My heater acted out years back and it was the splitter at the firewall. It was cracked and allowing loss of vacuum enough to not allow the selector to operate the blend door..... You can find stainless steel parts in the fish section at pet stores that will replace the plastic one FYI....
Kurt
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Joined: May 2003
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From: Salt Lake City, UT
I did get the control unit out and it checks out OK. So I ran vacuum from the engine compartement straight to the control unit, and it worked. So..apparently, the line was leaking between the cruise control unit and the main vacuum line. For now, I'm just going to run it without a cruise control until I have time to change that vacuum line set.
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