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Discussion Starter #1
I have a 1997 Caddilac Deville Concours and when I turn on my A/C it blows sometimes right away and other times I have Restart the car to make it work. I have tried turing on the heat and while that seems to comes through vents right away it's not on High like it's set on. After I turned on the Heat and drove for a bit the warm air finally blew on high and then I could turn the setting down to get A/C. Now since this was a few days ago and now the A/C nor the heat will not come on period. I have been told this sounds like the blower motor and I wondered what you guys thought. Also when I shut off everything from the control panel in the car I hear a clicking noise. Help!!
 

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99 Seville STS, 08 STS4 N* 1SG F55
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The blower motor does not always do what seems obvious in Auto mode, particularly if the car has not been running long. You need to pull the diagnostic codes and post - there should be some clue there. There's a lot of possibilities from your description, including the blower motor, fan speed controller, etc.
 

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Discussion Starter #3
Ok here are the codes I have and I went and looked to see what they mean:

P0401 - Exhaust Gas Recirculation (EGR) Flow Insufficient (current)
C1738 - Exhaust Solenoid Valve Short to GND (current)
B1971 - Inadvertent Power (History)
B2118 - Front Vertical Sensor Failed (History)
B0533 - Fuel Sensor Open/Shorted To B+ (History)

Ok I have no clue what any of that means and I hope that helps you.
 

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White Diamond '03 DHS (with DTS floor shift)
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Next time it does not seem to work, wiggle the connection at the blower motor on the firewall. It might be a bad connection. That said, if the connector is a little burnt, it is because the blower is on it's way out. Somewhat common. Been there, done that on my '97. Sometimes the blower goes into a purge mode (low fan) to purge moisture from the ducts when in A/C mode. When in heat mode, it will not come on till the ECT (Engine Coolant Temperature) reaches about 90 degrees.

None of those codes are related.
P0401 means that your EGR valve needs to be cleaned. Probably set the CHECK ENGINE light.
C1738 means that you have a short circuit in the ELC (Electronic Level Control) system and it is not working.
The other 3 are historical meaning that they have not failed in the last 3 ignition cycles. They may be intermittent failures.
 

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Discussion Starter #5
Thanks Ranger...Weird thing is after Pulled the codes the Blower decides to come one. Go figure. Now the connector that you say wiggle is that on the big silver thing that you see directly attached to the firewall when you open the hood. Also I was reading up on the B1971 - Inadvertent Power and it says it might be the relay so I wanted to know where that would be located. By the way what does the ELC system do and where is EGR Valve? Sorry for the questions I'm all new to this.
 

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White Diamond '03 DHS (with DTS floor shift)
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Blower motor is on the firewall next to the power brake booster. It should be black.

Not sure about the B1971, but there is a relay/fuse box on the left wheel house under the hood. Another in the trunk against the rear seat back (behind the trunk liner).

The ELC levels the rear end when a load is put in the rear seat or trunk via a compressor and air shocks.

EGR valve is between the brake booster and the TB on the crossover manifold. There is a "How To" in the Tech Tips section that has some pictures.
 

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I have a 1997 DeVille. I'm trying to test my blower motor. Three wire are connected to the blower motor. With fan speed on high, red is at 12 volts. Black is ground. What's the deal with grey. I never saw any power from the grey wire. Blower started off working some of the time, then none at all. This goes for heat and A/c. No burnt wires.. Shook connectors.I tried grounding the grey wire. (That was from somewhere else on the internet). How do you officially test the motor? Is this the right place to ask this type of questiion? If not I'm sorry. Please someone respond. Thank You.
 

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White Diamond '03 DHS (with DTS floor shift)
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One of those wires (might be the grey one) has variable voltage to control fan speed. Something like .04 - .09. Most likely the blower is toast. Somewhat common. I had to R & R it on my '97 Deville.
 
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