HOW TO: Convert CJ2 automatic -> CJ3 manual climate controls

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j91z28d1

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the code had to be pretty new. I've scanned it when I first got this scanner few months ago.


so here's what to have for bench testing. looks like they run on 5v?
 

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mikez71

mikez71

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The control (pin 6) is apparently 0V, 2.5V (to hold position) or 5V.
Pin 5 is 12V
Pin 10 is 5V source
Pin 9 - Position signal?

Hooked up Tech2 again today after unhooking battery.

aux mode was inverted from commanded position again.

aux temp did not move despite changing commanded temp..

aux mode was operating like this
roof vents for feet or defrost
no roof vents for face

QUIT moving after a cycle or two, probably quit after setting the usual codes.

hvac module info, broken camera
CE7553DE-F39E-486E-8EDE-39FF134F20CF.jpeg
 
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mikez71

mikez71

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Could not find these in '08 manual hvac diagrams..
Evap temp signal wire was already connected to the right pin from before. (J3-14)
Looks like I maybe missing evap temp sensor lo ref. (originally spliced with a bunch of temp sensor lo ref that went to

J3-14 WH EVAP TEMP SIGNAL (same as CJ2 auto version)
J3-19 TN LO REF - This wire not there, LO REF of evap sensor was spliced into other temp sensor lo ref and went to pin J2-16.

So I may need to connect one wire still..


Screenshot 2024-04-13 213602.gif

In the CJ2 auto wiring, the evap temp lo ref connects to J3-19
Screenshot 2024-04-13 160817.gif


Also missing 3 wires for rear temp controls, they are not needed if you do not have rear temp controls.
J1-9 OG aux mode signal
J1-10 YE aux temp signal
J2-11 GY 5V ref
 

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mikez71

mikez71

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OK, I plugged in another control unit. Seems to work. After using it a bit, there was no DTC. Will update after a few more cycles.
What I notice is the mode selector seems to have more positions, the old control unit would only blow up or down.
Now it moves through the (aux) blend positions properly, rear controls adjust temp properly as well.

So hoping it was a bad control unit..
 
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mikez71

mikez71

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DONE!

Have updated the first page with wire and pin location photos.
 
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