HVAC no comm
Thread Starter
Intermediate
Joined: Feb 2011
Posts: 32
Likes: 0
From: Santa Fe Texas
ok I am back. I came down with the flu shortly after starting into this project and have been laid up on the couch. Today I was able to move around some so I decided to take a look at the car.
I removed the battery and did some ohm readings. I have .307 between line feed of 21 and line feed of 22. I have OL between line feed of 18 and line feed of 21 or 22.
now here is where I get confused. is the fuse block not just a pass through? the reason I say this is because the bottom side of 18 has an orange wire that is hot all the time and I did a continuity test between the top side of 18 and the bottom side of 18 and everything seemed fine, but you can remove the green plug that would plug into the bottom side of fuse block, and still have HVAC controls if you give power to the fused side of 18 on the top. Does the fuse block separate? I am thinking it burned the circuit that feeds 18 from 21 and 22.
Any other suggestions?
I removed the battery and did some ohm readings. I have .307 between line feed of 21 and line feed of 22. I have OL between line feed of 18 and line feed of 21 or 22.
now here is where I get confused. is the fuse block not just a pass through? the reason I say this is because the bottom side of 18 has an orange wire that is hot all the time and I did a continuity test between the top side of 18 and the bottom side of 18 and everything seemed fine, but you can remove the green plug that would plug into the bottom side of fuse block, and still have HVAC controls if you give power to the fused side of 18 on the top. Does the fuse block separate? I am thinking it burned the circuit that feeds 18 from 21 and 22.
Any other suggestions?
Tech Contributor
Joined: Jan 2007
Posts: 19,528
Likes: 1,196
From: Dyer, IN
ok I am back. I came down with the flu shortly after starting into this project and have been laid up on the couch. Today I was able to move around some so I decided to take a look at the car.
I removed the battery and did some ohm readings. I have .307 between line feed of 21 and line feed of 22. I have OL between line feed of 18 and line feed of 21 or 22.
now here is where I get confused. is the fuse block not just a pass through? the reason I say this is because the bottom side of 18 has an orange wire that is hot all the time and I did a continuity test between the top side of 18 and the bottom side of 18 and everything seemed fine, but you can remove the green plug that would plug into the bottom side of fuse block, and still have HVAC controls if you give power to the fused side of 18 on the top. Does the fuse block separate? I am thinking it burned the circuit that feeds 18 from 21 and 22.
Any other suggestions?
I removed the battery and did some ohm readings. I have .307 between line feed of 21 and line feed of 22. I have OL between line feed of 18 and line feed of 21 or 22.
now here is where I get confused. is the fuse block not just a pass through? the reason I say this is because the bottom side of 18 has an orange wire that is hot all the time and I did a continuity test between the top side of 18 and the bottom side of 18 and everything seemed fine, but you can remove the green plug that would plug into the bottom side of fuse block, and still have HVAC controls if you give power to the fused side of 18 on the top. Does the fuse block separate? I am thinking it burned the circuit that feeds 18 from 21 and 22.
Any other suggestions?
Tech Contributor
Joined: Jan 2007
Posts: 19,528
Likes: 1,196
From: Dyer, IN
At this point, I don't know what to tell you. If you have an open between the line side of 21&22, and the line side of 18 , that's an issue. You already know you had 12 volts to 21 &22, and nothing to 18. Yes the fuse box does come apart, but I have not done it before.
Thread Starter
Intermediate
Joined: Feb 2011
Posts: 32
Likes: 0
From: Santa Fe Texas
well its fixed. I ordered a new fuse block and replaced it. Apparently it burnt the circuit in the fuse block between the 21, 22 and the 18 fuse on the feed side. Plugged everything in and worked like it was supposed to.
Thanks for the info
Thanks for the info
Tech Contributor
Joined: Jan 2007
Posts: 19,528
Likes: 1,196
From: Dyer, IN
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