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Correct way to disconnect battery?

14K views 6 replies 5 participants last post by  Blazernut 
#1 ·
So I never thought that disconnecting the battery for some maitenence would give me such a headache. I ended up having to replace my HVAC mode door actuator. I am just wondering if there is anything I can do in the future to avoid this problem.
Do I just need to turn off the HVAC system before disconnecting the battery? Maybe pull the HVAC B fuse before?
 
#2 ·
There's no solution other than putting a second battery in parallel with the main one if you replace it. If you need the vehicle totally powered down, such as to replace the alternator safely, there's no workaround.

There's also nothing you can do to get the vehicle "ready" to have the battery pulled. The failure of the HVAC actuators is a design flaw, and when you power the control module back up, it MUST recalibrate itself before any of the actuators will work. That recalibration process breaks many weak actuators. The designers should be ashamed.
 
#3 ·
So I bought a new replacement actuator. Are the replacements designed better?
The only reason I really would want to disconnect the battery in the future would be so that the PCM can relearn after doing maitenance. Is there any way of doing that without disconnecting the battery?
 
#5 ·
The only reason I really would want to disconnect the battery in the future would be so that the PCM can relearn after doing maitenance. Is there any way of doing that without disconnecting the battery?
I was wondering if you could disconnect the 3 connectors on the PCM and leave the battery hooked up.?? I know they say to disconnect the battery to change the PCM, but is that just the standard warning for when working on electrical compnents, or is there some damage possible?
 
#4 · (Edited)
Those actuator failures make me feel so paranoid at times. I am tempted to simply just disconnect the wiring off both left/right hot-cold actuators. Disconnect also the floorboard/front vents actuator. Defrost I will not touch as the humidity here frequently fogs my windshield early mornings.

In my area, the seasonal "winter" freeze seems typically four-six days tops. I never need my feet cooled or heated.

Being able force the defaults to just cold front vents, this would make me feel much better as the wear and tear to certain actuators has reduced.
 
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