1990 Town Car - no a/c only heat?

[VicCrownVic]

And he said he didn't know much!

I just have access to the information, lol.

+1 on what Sly said.

If it comes to replacement of the control head 90-94 CV/MGM will work and 90 to, I think, 92 TC will work (I know 93 TC is different, but I've got no info on 91-92).

If a bad BDA is capable of burning out the control head I wonder if you would see noticeable scorching on the PCB if you trace the pins you tested?

[drhill]

All good info - I will check the inside of the ATC when I get back home on Sunday. It's weird, now the BDA has moved again slightly and is not full AC anymore - but also not full heat.

Definitely seems like an electrical glitch now that the door has moved twice.

[drhill]

Ok, I opened up the ATC and here is what I found on the circuit board....looks like one of the capacitors, resistors or whatever leaked quite a bit. Any of you guys know electronics and which one might be leaking?






I assume this is my issue...best to just get another ATC at this point?

OR - is this maybe something a failing BDA could have caused? I'd rather not change the BDA if I can help it...


Thanks for the opinions and advice!

[gadget73]

Looks more like glue used to secure things. If the leads are green and fuzzy, thats leaking magic capacitor juice. They might still be bad though.

How do the mechanicals in the BDA look?

[drhill]

There is one area of green on the board near one of the resistors - you can see it streaked down but It's not coming from a capacitor I don' think? I didn't pull the BDA because of how buried it is in the dash, I'd have to take down the whole dash to get to it...I'm trying to avoid that if I can since I don't have that much time right now.

I may grab a good looking Junkyard ATC and try it out unless you guys think this one looks good. It didn't seem to deliver the right voltage during the testing. Just trying to replace the right thing...

[gadget73]

Looks more like marker. When it has corrosion, its green or blue and fuzzy like a bad battery cable. The only two caps that are the failure prone type I see are around the glue, one is a red body the other is purple. Nothing else on that board is anything that typically goes bad from age or heat.

[sly]

+1 the yellow stuff is glue. And those caps look fine from what I can see in the pics. The usual issue with these isn't so much the controls, but the connections. Oxidation and corrosion can be an issue. and if the solder joints on the board to the pins are cracked, that would be the issue. The components all look ok. I'd look real close at the solder joints and make sure they all look good with no cracks. Other than that, hose the connector with contact cleaner and call it good and put it all back together and continue checking out the BDA. The reason I think a connector issue is because stuff started sorta working after you probed stuff.