Power Transistor is to control blower motor and input the signal into a HVAC control module.
This diagnostic procedure supports the following DTC :
DTC B0193 Blower Motor Speed
Ignition is ON.
| • | The blower motor operating voltage is less than 5.0 V, actual blower motor feedback voltage, than 9.0 V of blower motor operating voltage. | 
| • | The blower motor operating voltage is greater than 9.0 V, actual blower motor feedback voltage, than 5.0 V of blower motor operating voltage. | 
| • | The HVAC control module detects that the blower motor control circuit is open. | 
The inside air temperature sensor value setting is 25 degrees.
| • | The DTC will become history if the HVAC control module no longer detects a fault. | 
| • | Ignition is ON or OFF. | 
| • | The DTC can be cleared with a scan tool. | 
The number(s) below refer to the step number(s) on the diagnostic table.
Level  | Voltage  | 
|---|---|
0  | 0  | 
1  | 4.0  | 
2  | 4.5  | 
3  | 5.0  | 
4  | 5.5  | 
5  | 6.0  | 
6  | 6.5  | 
7  | 7.0  | 
8  | 7.5  | 
9  | 8.0  | 
10  | 8.5  | 
11  | 9.0  | 
12  | 9.5  | 
13  | 10.0  | 
14  | 10.5  | 
15  | Max  | 
Step  | Action  | Value(s)  | Yes  | No  | 
|---|---|---|---|---|
1  | Did you perform the Diagnostic System Check - Vehicle?  | --  | Go to Step 2  | |
2  | Test the appropriate power transistor assembly signal circuit of the power transistor assembly for a short to ground. Did you find and correct the condition?  | --  | Go to Step 8  | Go to Step 3  | 
3  | Test the appropriate signal circuit of the power transistor assembly for a short to voltage, a high resistance, or an open. did you find and correct the condition?  | --  | Go to Step 8  | Go to Step 4  | 
Test the voltage power transistor and change each level. Did you find and correct the condition?  | --  | Go to Step 8  | Go to Step 5  | |
5  | Inspect for poor connections at the harness connector of the power transistor assembly. Did you find and correct the condition?  | --  | Go to Step 8  | Go to Step 5  | 
6  | Inspect for poor connections at the harness connector of the HVAC module. Did you find and correct the condition?  | --  | Go to Step 8  | Go to Step 7  | 
7  | Replace the power transistor assembly. Did you complete the replacement?  | --  | Go to Step 8  | --  | 
8  | 
 Does the DTC reset?  | --  | Go to Step 2  | System OK  |