Pinpoint Test V: Dual Generator Lower Circuit Fault Detected (P1149)

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.

V1 CHECK THE LOWER GENERATOR 1 CIRCUIT FOR A SHORT TO VOLTAGE
- Key in OFF position.
- Disconnect: PCM C1381c.
- Disconnect: Lower Generator C1251a.
- Key in ON position.
- With the key ON, engine OFF, measure the voltage between the PCM C1381c pin 4, circuit 1185 (YE), harness side and ground.
  
  Fig 1: Checking Lower Generator 1 Circuit For A Short To Voltage
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 0 volts?
- Yes : REPAIR the I circuit 1185 (YE). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
- No : GO to V2.
V2 CHECK THE LOWER GENERATOR I CIRCUIT
- Key in OFF position.
- Connect: Lower Generator C1251a.
- Connect: PCM C1381c.
- Key in START position.
  NOTE: After starting the engine, wait at least 2 minutes for the glow plugs to stop cycling.
  
  With the key ON engine running, measure the voltage between the C1251a pin 1, I circuit 1185 (YE), harness side and ground.
- Is the voltage greater than 0 volts?
- Yes : GO to V4.
- No : GO to V3.
V3 CHECK THE PCM OPERATION
- Key in OFF position.
- Connect: PCM C1381c.
- Key in ON position.
- With the key ON, engine OFF and the lower generator C1251a still disconnected, carry out a glow plug test with the diagnostic tool (See INTRODUCTION -- 6.0L DIESEL article for test procedures). Measure the voltage at the lower generator C1251a pin 1, I circuit 1185 (YE) harness side and ground while carrying out the glow plug test.
  
  Fig 2: Measuring Voltage Between Connector And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 0 volts with the glow plugs on?
- Yes : GO to V4.
- No : INSTALL a new lower generator. REFER to GENERATOR AND REGULATOR . CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
V4 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Check for:
  - corrosion
  - pushed-out pins
- Connect all the PCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes : INSTALL a new PCM. REFER to ELECTRONIC ENGINE CONTROLS - DIESEL ENGINE . CLEAR the DTCs. REPEAT the PCM self-test. TEST the system for normal operation.
- No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.