No A/C...general TS

[dnsherrill]

on the white car, 96 base
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after repairing BDA and reassembling dash and interior I've noticed (with EATC OFF) air is flowing from the dash vent while moving; if i stop moving, air stops from the dash...even with a temp of 50deg outside the air is warm, like it's coming off the engine;
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today it's pretty warm (75ish) and with the blk interior it's even warmer in the car; turn to MAX AC.....air blows but not cold; turn to AUTOMATIC set at 65 deg....same thing, lots of uncooled air from the dash, not much if anything from the other registers
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it's possible the EATC is from a different car, it is a soft button, so it's either from a 95 or 96
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where to start trouble shooting? confirm compressor is coming on? check freon?
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the good news: I changed the BDA to have heat, I got that!

 

[Lownslowlsc]

Did you check the wiring next to the front strut tower?

 

[dnsherrill]

not yet, but the power windows still work

 

[soduka]

Does the radiator fan kick on when you turn it to Max A/C? Is the clutch/compressor kicking on? If no (or yes, either way really since we know there's a problem), check system pressure at the low side port against the passenger side firewall. If it reads zero, there's at least part of it.

 

[dnsherrill]

Does the radiator fan kick on when you turn it to Max A/C? Is the clutch/compressor kicking on? If no (or yes, either way really since we know there's a problem), check system pressure at the low side port against the passenger side firewall. If it reads zero, there's at least part of it.

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I haven't had time to check the compressor or system pressure yet; I think there's a glitch with air distribution; whether it's on Max AC or on 90 deg heat, air is only distributed from the long vent on top of the dash cover (the defrost supply vent), nothing from the floor or from the vents adjacent the message display ctr.
I replaced the BDA because it wasn't making heat; now it makes heat, but I'm wondering if i screwed something else up doing the swap; I think the AC was working last summer, when the heat wasn't; as mentioned- now, even with the EATC OFF, warm air comes from the dash top vent when the car is moving, when the car stops, the air stops

 

[Duck]

Sounds like you knocked off the yellow hose at the blend door solenoid. It goes from the ETAC to the solenoid.

 

[dnsherrill]

Sounds like you knocked off the yellow hose at the blend door solenoid. It goes from the ETAC to the solenoid.

thanks Duck, what does the BD solenoid control? When I put the good BDA in I tested for heat before reattaching the dash. It was too cold to check AC then

 

[chris2523]

the AC stuff is vacuum controlled. if you have no vacuum, because you knocked the hose loose, the systems "safe default" is heat on the windshield, defrost.
annoying in the summer, but absolutely crucial in the winter.

 

[98lincmk7lsc]

FYI: soft button EATC's are from 93 or 94 only

 

[chargerxr]

First thing to check is the vacuum hoses that attach to the back of the eatc. It's easy to pull out and check to see if vacuum hoses came loose from eatc.

 

[dnsherrill]

FYI: soft button EATC's are from 93 or 94 only

???? both my 96s had the same type EATC face...I call them 'soft button'----
maybe I got lucky and the vac leak is at the EATC not back up in the dash; on a different note, the Brown Car has correct pos pressure air distribution, but the a/c is not cold...hopefully the system just needs charging

 

[Myco]

Like someone said there must be a vacuum leak somewhere. The vacuum leak makes it default blowing on the dash. The best way to figure out where the vacuum leak is is to have the vacuum system "smogged" or "smoked" by a shop. If it was working before you put in the new dash unit it's pretty safe to say that the EATC is the problem or one of the hoses on the back got loose. ( but I wonder what was wrong with the previous EATC?) The yellow vacuum tube that connects to the back of the eatc connects behind the dash and can come loose very easily causing this problem. Some people say you need to pull the dash to get to it but I have reached it from laying on the drivers side floor and reaching up and behind the dash and feeling around for it. Before I went and trouble shooted the problem I would first make sure it's not the EATC. When I had this problem my EATC was being replaced with one where the buttons were all cracked. The EATC I put in was bad though and I was told it was good... I ended up chasing my tail when it was the 'new' EATC that was the culprit.

 

[dnsherrill]

eh, swapped eatc's (a known good unit) same result, hoses and connections look solid behind the eatc and into the dash; I guess next is tracing the yellow hose. I did notice that when I turn to MAX AC the fan speeds up but the compressor does not come on....I'm not certain, but it looks like the compressor may be leaking oil

 

[dnsherrill]

the service manual distinguishes a small vs large leak; I have a small leak since it only blows while accelerating, my eatc is good, the connections at the eatc are good
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the compressor is not coming on in MAX AC or in DEF mode. Is that normal with the vac leak?
gonna take it in for a no charge system test before pulling the dash again

 

[dnsherrill]

anyone know if I can find the vac leak with a tester (Mighty Vac style) on each of the 5 (R,W,BL,W,Y) hoses coming off the EATC?

 

[dnsherrill]

could improper installation of the BDA cause the system to go into failsafe mode;
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[dnsherrill]

where is the AC vacuum check valve located???
It has three ports:
1 for the intake manifold one for the reservoir and one for the control assembly/eatc. Is it located behind the passenger wheel well liner?

 

[dnsherrill]

thankfully i found the vac check valve (behind pass front fender liner) before pulling the dash again, my leak was plain as day; somehow one of the lines (to the EATC) had been forcibly removed from the check valve; made the connection, problem solved re; getting out of fail-safe mode

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no idea how this happened

 

[olddavid]

I am glad you solved this problem publicly - it was good schooling for all of us, and I especially appreciate the diagram. Pictures are good.

 

[dnsherrill]

this fix is somewhat of an anomaly....i mean, how in the HEEL did that vac line at the check valve get knocked off of there? at least i didn't pull the dash needlessly