Pinpoint Test M: The Blower Motor Is Inoperative - Manual Climate Control

WARNING: This page is about a different car, the 2005 Ford Pickup, 2005 Ford F550 Super Duty, 2005 Ford F450 Super Duty, and 2005 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

M1 CHECK A/C BLOWER MOTOR CIRCUIT 181 (BR/OG) FOR VOLTAGE
- Disconnect: Blower Motor C1227.
- Key in ON position.
- Turn the function selector switch to the FLOOR position and turn the blower motor switch to HIGH.
- Measure the voltage between A/C blower motor connector C1031, circuit 181 (BN/OG) and ground.
  
  Fig 1: Checking For Voltage To Blower Motor
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
- Yes : GO to M2.
- No : GO to M3.
M2 CHECK CIRCUIT 261 (OG/BK)
- Key in OFF position.
- Measure the resistance between A/C blower motor connector C1031, circuit 261 (OG/BK) and ground.
  
  Fig 2: Measuring Resistance Between A/C Blower Motor Connector 1031 Circuit 261 And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : INSTALL a new blower motor. TEST the system for normal operation.
- No : GO to M5.
M3 CHECK CIRCUIT 296 (BK/LG) FOR VOLTAGE
- Key in OFF position.
- Disconnect: Blower Motor Relay.
- Key in ON position.
- Measure the voltage between blower motor relay socket pin 85, circuit 296 (BK/LG) and ground.
  
  Fig 3: Checking Circuit 296 (BK/LG) For Voltage
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
- Yes : GO to M4.
- No : REPAIR circuit 296 (BK/LG). TEST the system for normal operation.
M4 CHECK CIRCUIT 399 (BR/YE)
- Key in OFF position.
- Measure the resistance between blower motor relay socket pin 86, circuit 399 (BR/YE) and ground.
  
  Fig 4: Checking Circuit 399 (BR/YE)
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : INSTALL a new blower motor relay. TEST the system for normal operation.
- No : GO to M7.
M5 CHECK CIRCUIT 57 (BK)
- Disconnect: Blower Motor Switch C294c.
- Measure the resistance between blower motor switch C294c, circuit 57 (BK) and ground.
  
  Fig 5: Checking Circuit 57 (BK)
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : GO to M6.
- No : REPAIR circuit 57 (BK). TEST the system for normal operation.
M6 CHECK CIRCUIT 261 (OG/BK)
- Measure the resistance between blower motor switch C294c, circuit 261 (OG/BK) and blower motor C1031, circuit 261 (OG/BK).
  
  Fig 6: Checking Circuit 261 (OG/BK)
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : INSTALL a new blower motor switch. TEST the system for normal operation.
- No : REPAIR circuit 261 (OG/BK). TEST the system for normal operation.
M7 CHECK CIRCUIT 57 (BK)
- Disconnect: Function Selector Switch C294a.
- Measure the resistance between function selector switch C294a pin 4, circuit 57 (BK) and ground.
  
  Fig 7: Checking Circuit 57 (BK)
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : GO to M8.
- No : REPAIR circuit 57 (BK). TEST the system for normal operation.
M8 CHECK THE BLOWER MOTOR RELAY GROUND CIRCUIT 399 (BN/YE)
- Measure the resistance between blower motor relay connector pin 86, circuit 399 (BN/YE) and function selector switch C294a pin 3, circuit 399 (BN/YE).
  
  Fig 8: Checking Blower Motor Relay Ground Circuit 399 (BN/YE)
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : INSTALL a new function selector switch. TEST the system for normal operation.
- No : REPAIR circuit 399 (BN/YE). TEST the system for normal operation.