This might come in handy for 92 and 93 SSEi'* that didn't get a volt meter in the dash, eh? I did that a couple times before I added a gauge to mine.

Not to take this back off subject but:

The sale is good 'til January 31st.

OK, back on topic now...

Thanks Will. I'll see what I can do with it this evening. I may have some questions about the procedure for adjusting the air mix door (assuming I get that far, or that its necessary). I'll post my findings tomorrow.

In the meantime, is it normal for the ECC to drive the mix door to hot every time the car is started? Or is that a function of the error code that'* set? I hadn't paid attention when it was working properly, but I think the fan stays on it'* lowest setting for a few seconds after engine start so if the door moved to hot then to the set position I'd probably never know. Jus' wonderin'.

Update:
Just talked to my wife, who drives the Bonneville 90% of the time, and she was not impressed with the heater output this morning. She performed the maneuver that I thought would get her into a “normal” state of operation, i.e. start car, wait for flashing display to quit, run temp setting to 60, set temp to 90, then set to desired temp. There’* a fair to moderate chance she’* low on coolant, but there’* also a chance that what I think is the full hot position for the air mix door is not.

So, for those of you who’ve witnessed a normally operating air mix actuator, I’m asking how far the arm moves from stop to stop. As I remember, mine’* moving roughly 90 degrees. It stops moving to the right just after it passes the hole which you can see the arm through. Does that sound about right? Or should it move farther to the right?

If you look at the 1st picture of the dismantled dash (with the red arrows) posted by randman1 in the thread “Need help with AC with Electronic Climate Control” started by 98SSE, the location of the air mix door lever in that picture is about where mine stops at full hot. Is the lever at its right-most position in the picture?

The ECC diagnostics squawked a “00”, so I guess I’m going after the HVAC Controller. That seems reasonable since it seems like the ECC has lost its mind. Out of all the things that could go wrong with the system, I’m going to guess that this is the most expensive to remedy. I would expect nothing less. How difficult is it to replace this unit – is it easier to access than the air mix controller?

Here’* a strange data point. When my wife drove the car yesterday and set the temperature like I told her to, she claimed she was getting lukewarm air. (Coolant level was fine, BTW). I drove the car last night just like she would – start it, throw it in gear, and take off down the road. I then adjusted the temperature on the fly, waiting for the flashing to stop, setting the temp at 60, then setting it at 90. I’m not sure I’d classify the air coming out the heater vent as lukewarm. I’d call it COLD. When I got to the school I checked the position of the air door arm and, sure enough, it was dang near full cold. After we were done at the school, I used the same procedure to pump warm air out of the heater only this time I didn’t take the car out of Park until I was done with the routine on the ECC. I was rewarded with heat all the way home. What in tarnation is the relationship between the vehicle moving and the operation of the ECC?

It’* probably a moot point, but I’m going to do some more testing before I change the HVAC Controller. I think I’ll have my wife drive me around while I play with the ECC. Does the car have to be moving or just put into gear? If I set the temp on the fly, then stop and put it in Park, can I reset it and get heat or do I have to shut it off? I have to know. For no other reason than just to know.

Maybe I’ll have my wife pull into McDougal’* while I’m tinkering and I’ll buy her a Happy Meal. Then I can call it a date.

I've GOT to get me one o' them FSMs! I took a look at the rest of the diagnostic features Will mentioned and there'* some cool information there. I just don't know how to decode it. It'* like showing a dog a scratch-n-sniff picture of a rack of ribs - now I'm salivating and won't be satisfied until I have the whole enchilada.