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Discussion Starter #1
Hi - I have a problem with my front A/c and blower. Both are not working. The rear fan is working but no cold air.

I replaced the transistor assembly as suggested in this forum and was able to make the front and rear a/c and fan working for about 15 minutes.

During this time I did not put back the transistor assembly back from where I took it off but just plugged the connection.
The a/c suddenly stopped and the unit was really hot.

I would like to know if there is a way to find out what caused the a/c to trip. What would be the way to go about to diagnose this issue ?

Thanks
 

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Here's some info from the service manual that may help to at least retrieve a code:

The climate control unit has a self-diagnostic function. To run the self-diagnostic function, do the following:

1. Turn the ignition switch ON (II).

2. Press the AUTO button and then the OFF button.

If there is any abnormality in the system, the temperature indicator will light up the segment (A through N) corresponding to the error. The temperature indicator will then alternate every second between displaying ''88'' (all segments lit) and the error code segment (A through N).

NOTE: The system will only display the DTC when the AUTO and OFF buttons are pressed. If you release the buttons, the display will go blank. To return the display, simply press the AUTO then the OFF buttons again.

To determine the meaning of the DTC, refer to the DTC Troubleshooting Index. If there is no abnormality, the segments will not light up.

NOTE: If there are no DTCs detected (no opens or shorts in the climate control circuits or sensors), and the system is still not operating properly, check the sensor input to the climate control unit.

3. Turn the ignition switch OFF to cancel the self-diagnostic function. After completing repair work, run the self-diagnostic function again to make sure that there are no other malfunctions.

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The rear heater-A/C control panel-unit also has a self-diagnostic function. To run the self-diagnostic function, do the following:

1. Turn the fan switch OFF.

2. Turn the ignition switch ON (II).

3. Turn the rear A/C manual switch ON.

4. Press the vent switch and then the heat switch. Continue to hold both switches down until the vent indicator comes on for two seconds, then it will blink the diagnostic trouble code (DTC) to indicate a faulty component. If no DTCs are found, the indicator will not blink after the initial two seconds light.

5. Turn the ignition switch OFF to cancel the self-diagnostic function. After completing repair work, run the self-diagnostic function again to make sure that there are no other malfunctions.
 

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Discussion Starter #3
I ran the diagnostics and did not come up with any error. How do I check the sensory input to the climate control unit ?
After changing the transistor assembly to a new unit, the A/c did run for sometime before tripping.


How I do check if the transistor assembly that I replaced is burned/tripped ?

Thanks for your help,
 

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If the part you put in is new, that's highly unlikely. If it's getting hot, that usually means the draw on the unit is way over and above what it's designed to handle....similar to trying to drink a thick milkshake through a straw. I'm almost wondering if you have a seized blower motor....
 

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Discussion Starter #5
Do you mean a partially functional blower motor ? Just as a try out, I jumped my old transistor assembly and it is now running a/c. I had a even before problem where the fan was not blowing to its full capacity unless I put it in the highest level. So it is working as it was before but not normally I think.

I ordered the parts for fixing the transistor assembly and am planning to fix the transistor assembly. I was also thinking of doing a "A/C Pro" to recharge the A/C as well. Any thoughts on that ?
 

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At first you said you replaced the transistor assembly and it didn't work, but you put the old one back in and jumpered it and it *did* work....and then you're mentioning repairing the transistor assembly.

I'm totally confused.....
 

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Discussion Starter #7
oh sorry. Yes I jumped the old transistor assembly but did not want to leave it like that but instead solder in the new part that I ordered instead of leaving it like that (jumped I mean).

But as I said, even with the jumped wire inplace, the A/C is not fully functional meaning the the fan is blowing not much air in the lower settings and it is not cooling fast enuf etc.

Hope that clarifies it a bit.
 

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If the old transistor is still in place, you can't jump one in on top of it and hope it works unless it reads totally open...and even then with voltage applied it may behave differently. Replace it and see what happens.
 

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So I replaced the thermal cut off fuse and now it looks like I may have blown the fan capacitor. Hopefully switching this out works. When I jump the capacitor the AC kicks on and the fan runs full blast. Sounds like that's the problem anyway. Part is ordered 7 days till i receive it. I'll keep posted.
 
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