Chrysler Repair: 95 NY ATC unit, pin joints, head communication

Question
NY has same problem as others, according to this site. It blows hot air and display is blank. If I bang the console with a screw driver, it will usually work properly. This happens every day. I performed the diagnostic test by pushing in the buttons and came up with a 36 from the first test row. I don't get any response from the second row, first button test. Is it still the ATC unit, or maybe a loose connection? This site has been a relief-Thank you
Connie!

Answer
Hi Connie,
The first place I would look is at the '8-pin black square' plug and socket on the back side of the atc unit. There are two wires on pins 3 and 4 (violet/brown and white/black) that are the head communication wires of "head communication failure" code 36. My suspicion is that the pins of the socket which are soldered to the internal circuit board of the controller have gotten intermittently detached from the circuit board. The attachment is accomplished by solder, so if you have or get a soldering pen at an electronics store and touch the tip of the pen to each of the pin joints so as to reheat the solder it will reattach the pin to the board and end the intermittent problem.
To remove the control, if necessary remove the ash receiver, then gently pry off the surround bezel, then you will see screw on either side of the panel which you then remove, and the pull out the panel and while so-doing remove the plug. Then open the unit if necessary to gain access to the pins of the socket where they attach to the circuit board and do the solder 'touch-up'.
If you had an ohmmmeter you could validate a good connection from the pin to the board. You might also buy a small package of solder to apply simultanieously when the solder pen is in contact with the joint. But probably simply reheating it will do the job. You will see the solder turn to liquid when it heats, then you remove the tip and it reset to a solid.
Roland