Post Number: 25
|Posted on Sunday, 17 April, 2022 - 12:59:
Hey guys I've looked everywhere in the manuals I have and can't find a wiring diagram for the heating and cooling system fans. All of a sudden my A/C switch doesn't activate the dash fans. No LOW or HIGH fans at all. I have power to the fuse and the fuse is good but I need a wiring diagram to get further along.
Any help appreciated.
Post Number: 3280
|Posted on Monday, 18 April, 2022 - 01:00:
Having the year, make, & model, or the VIN or
SZ Chassis Number Derivation from VIN, would be of great assistance to your potential assistants.
Post Number: 26
|Posted on Monday, 18 April, 2022 - 03:35:
YOU ARE CORRECT MY MISTAKE FOR NOT PUTING IT IN MY POST! Thanks
1986 Spirit SCA2S42A8GCX 14618 North American market car.
I tried swapping out each relay (fan control, fan switch off and ac control but no change.
This system was working, lost freon charge and was partially recharged (80 psi on both gages) but had no fans OR A/C clutch engagement for some reason.
Found the 10 amp fuse (B5)THAT LOOKED GOOD visually that actually all of a sudden had no continuity between its legs. Replaced it and had clutch engagement BUT still no a/c fans inside.
Its weird as everything was working fine until the freon charge was lost slowly over several weeks.
As I sit now, we have clutch engagement but no position of the a/c switch will turn on fans inside.
I can't imagine that the fan delay switch on the thermostat housing all of a sudden froze in the closed position at the same time the 10 amp fuse had its issue. I haven't checked the delay switch yet. It looks as if I disconnect it the open circuit would mimic the switch opening (at 44C) and allow the fans to run EXCEPT that the lower air deflectors have to be all the way open for its micro witch to close allowing the fans to run.
I really need a wiring diagram so I an trace wires and find where the electricity stops.
No wiring diagram I have shows this circuit (unless I'm blind which could be)
Post Number: 743
|Posted on Monday, 18 April, 2022 - 05:28:
Post Number: 4083
|Posted on Monday, 18 April, 2022 - 09:29:
Have forwarded documentation on the Shadow II automatic air conditioning system that may help you.
Post Number: 27
|Posted on Monday, 18 April, 2022 - 10:20:
michael- Thank you for trying but TSD4400 doe not have the wiring diagrams needed.
David- Thank you and I am reading the docs as we converse here
Post Number: 744
|Posted on Tuesday, 19 April, 2022 - 03:58:
Posted on the other site ok
Post Number: 28
|Posted on Tuesday, 19 April, 2022 - 10:57:
OK so in tracing wiring I find I'm down to finding the Voltage stabilizer and fan speed module to see if power comes into that unit to go to the fans. Its not where the wiring diagrams for the SY say it is.
I get a/c clutch engagement but no fans so the juice seems to stop at the fan speed module BUT all of the info I have and have been given doesn't locate that module in MY SZ (not 20,000+ or SY)
Does anyone have further wiring or location diagrams that show this unit in SZs?
Maybe mine is a unicorn being it has FI and not carbs? :-)
Really working to find where the juice stops.
I feel like I'm reading a plate of spaghetti looking at all these wiring diagrams
And I thank all for the help so far on this issue
Post Number: 29
|Posted on Wednesday, 20 April, 2022 - 08:41:
After looking at another wiring diagram I have tested for power down to pin 30 fan control relay and have same.
I have lifted the 14UB wire off of the fan switch off relay and no fans run
I have lifted the oil pressure wire from its switch to simulate engine running and lifted the water temp wire from its pin to simulate hot engine (44 C) and still no fans run.
I have replaced the fan control relay also.
Need some more input or ideas from anyone who has
real knowledge of this system
THANKS to all who are trying to help
Post Number: 75
|Posted on Sunday, 11 September, 2022 - 17:44:
Replacing the fan control module fixed the issue