Cadillac: Blower Motor?, exact diagnosis, diagnostic charts

Question
oops.  1999 deville, 4.6L, factory A/C.
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Followup To

Question -
No air flow.  Turned A/C on by hitting "Auto", heard engine load and A/C start like normal.  No air flow.  Manually turned the fan speed to high, nothing, then low, nothing.  Tried Econ, nothing.

Tried Heat (turned up thermostat), same symptoms.  

Swapped the two relays (fuel pump and A/C comp), no change.  Swapped all other fuses I could think would be related, no change.

Is it the blower motor?  (Also, can't hear the aux blower to the rear seats do anything either).

Answer -
The YEAR and MODEL would be nice to know.

Answer
The only component that has a common controller is the AC-Heater programmer (also called the ACM). It is possible that the ACM is faulty and or you have 2 seperate issues with both blower motors.

There are diagnostic charts and tests that need to be performed before an EXACT diagnosis can be made.

If your only problem was with the front blower I would have to say that the blower is most likely at fault.

ut with the rear blower also being inoperative this may not be the case.

If your SURE you can't feel any blower movement or hear the rear fan running yu will have to do the diagnostics on the ACM.

If you CAN feel the fan moving in the rear I would say that you need to replace the front blower.

I can provide you with all the necessary tests to be performed, But you will have to contact me at:

onlineautohelp@msn.com