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Pinpoint Test

NOTE: Make sure battery voltage is greater than 12.2 volts prior to carrying out this pinpoint test.
NOTE: Do not have a battery charger attached during vehicle testing.
  1. CHECK THE BATTERY CONDITION
    1. Carry out Battery Condition Test to determine if the battery can hold a charge and is OK for use. REFER to DIAGNOSTIC ROUTINE A 
      • Does the battery pass the condition test? 
      • Yes:  GO to step 2 .
      • No:  INSTALL a new battery. REFER to BATTERY .
  2. CHECK THE GENERATOR CONNECTIONS
    1. Ignition OFF.
    2. Disconnect and inspect all generator connectors.
    3. Repair:
      • corrosion (install new connector or terminals - clean module pins)
      • damaged or bent pins - install new terminals/pins
      • pushed-out pins - install new pins as necessary
    4. Connect the generator connectors. Make sure they seat, latch correctly and are tightened to specification. REFER to TORQUE SPECIFICATIONS .
    5. Measure and record battery voltage at the battery.
    6. Measure:
      Fig 1: Checking Generator Connections
      G07428574Courtesy of FORD MOTOR CO.
      • Is the voltage within 0.5 volt of recorded battery voltage? 
      • Yes:  GO to step 3 .
      • No:  VERIFY the fusible links are OK. If OK, REPAIR the circuit. If not OK, REFER to the SYSTEM WIRING DIAGRAMS to identify the possible causes of the circuit short.
  3. "A" SENSE CIRCUIT LOAD TEST
    NOTE: The following step uses a test light to simulate normal circuit loads. Use only the test light recommended in the Special Tools table at the beginning of this section. To avoid connector terminal damage, use the Flex Probe Kit for the test light probe connection to the vehicle. Do not use the test light probe directly on any connector.
    NOTE: This step puts a load on the "A" sense circuit. If there are corroded or loose connections, loading the circuit may help show the fault. A 250-350 mA incandescent 12-volt test lamp is required for this step. This circuit will not be loaded properly using an Light-emitting Diode (LED)-style test lamp.
    1. Disconnect: Generator C102A.
    2. Using a 12-volt test lamp, check for voltage:
      Fig 2: Checking Generator Voltage
      G07428575Courtesy of FORD MOTOR CO.
      • Does the test lamp illuminate? 
      • Yes:  GO to step 4 .
      • No:  VERIFY Battery Junction Box (BJB) fuse 58 (10A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the SYSTEM WIRING DIAGRAMS to identify the possible causes of the circuit short.
  4. CHECK THE GENERATOR MONITOR FREQUENCY (GENMON_HZ) Parameter Identification (PID)
    1. Connect: Generator C102A.
    2. Start the engine.
    3. Using a scan tool, view the Powertrain Control Module (PCM) Parameter Identifications (PIDs).
    4. Monitor the GENMON_HZ Parameter Identification (PID).
      • Does the Parameter Identification (PID) read between 80-200 Hz? 
      • Yes:  GO to step  8 .
      • No:  GO to step 5 .
  5. CHECK THE GENERATOR MONITOR FREQUENCY (GENMON_HZ) Parameter Identification (PID) WITH GENERATOR DISCONNECTED
    1. Ignition OFF.
    2. Disconnect: Generator C102A.
    3. Start the engine.
    4. Using a scan tool, view the Powertrain Control Module (PCM) Parameter Identifications (PIDs).
    5. Monitor the GENMON_HZ Parameter Identification (PID).
      • Does the Parameter Identification (PID) read between 0-2 Hz? 
      • Yes:  GO to step  7 .
      • No:  GO to step 6 .
  6. CHECK GENERATOR MONITOR CIRCUIT
    NOTE: This pinpoint test step directs testing circuits using a back-probe method. Use the special back-probe tool specified in the tool list in this information. Do not force test leads or other probes into connectors. Adequate care must be exercised to avoid connector terminal damage while making sure that good electrical contact is made with the circuit or terminal. Failure to follow these instructions may cause damage to wiring, terminals, or connectors and subsequent electrical faults.
    1. Ignition OFF.
    2. With Powertrain Control Module (PCM) C175B connected, carefully back-probe and connect a fused jumper wire:
      Fig 3: Checking Generator Monitor Circuit
      G07428576Courtesy of FORD MOTOR CO.
    3. Start the engine.
    4. Using a scan tool, view the Powertrain Control Module (PCM) Parameter Identifications (PIDs).
    5. Monitor the GENMON_HZ Parameter Identification (PID).
      • Does the Parameter Identification (PID) read 0 Hz? 
      • Yes:  INSPECT the harness for wire to wire shorts or insulation chaffing, mis-pinned connectors and correct wire colors and REPAIR the circuit as needed.
      • No:  GO to step  9 .
  7. MONITOR THE GENERATOR MONITOR FREQUENCY (GENMON_HZ) Parameter Identification (PID) WHILE ACTIVATING THE GENERATOR VOLTAGE DESIRED (GENVDSD) Parameter Identification (PID)
    1. Ignition OFF.
    2. Connect a fused jumper wire:
      Fig 4: Connecting Jumper Wire Between Generator Pin 1 And 2
      G07428577Courtesy of FORD MOTOR CO.
    3. Start the engine.
    4. Using a scan tool, view the Powertrain Control Module (PCM) Parameter Identifications (PIDs).
    5. With the engine running at idle, set the active command GENVDSD Parameter Identification (PID) to 14 volts.
    6. Monitor the GENMON_HZ Parameter Identification (PID).
      • Does the Parameter Identification (PID) read between 120-130 Hz? 
  8. CHECK THE GENERATOR COMMAND LINE FAULT (GENCMD_LF) Parameter Identification (PID)
    1. Start the engine.
    2. Using a scan tool, view the Powertrain Control Module (PCM) Parameter Identifications (PIDs).
    3. With the engine running and all selectable loads OFF, monitor the GENCMD_LF Parameter Identification (PID).
      • Does the Parameter Identification (PID) fluctuate from YES FAULT to NO FAULT? 
      • Yes:  INSTALL a new generator. REFER to GENERATOR - 3.5L TI-VCT .
      • No:  The system is operating correctly at this time. The concern may have been caused by an intermittently loose or corroded connector. ADDRESS the root cause of any connector or pin issues.
  9. CHECK FOR CORRECT Powertrain Control Module (PCM) OPERATION
    1. Ignition OFF.
    2. Disconnect and inspect all Powertrain Control Module (PCM) connectors.
    3. Repair:
      • corrosion (install new connector or terminals - clean module pins)
      • damaged or bent pins - install new terminals/pins
      • pushed-out pins - install new pins as necessary
    4. Reconnect the Powertrain Control Module (PCM) connectors. Make sure they seat and latch correctly.
    5. Operate the system and determine if the concern is still present.
      • Is the concern still present? 
      • Yes:  CHECK On-Line Automotive Service Information System (OASIS) for any applicable Technical Service Bulletins (TSBs). If a Technical Service Bulletin (TSB) exists for this concern, DISCONTINUE this test and FOLLOW the Technical Service Bulletin (TSB) instructions. If no Technical Service Bulletin (TSB) address this concern, INSTALL a new Powertrain Control Module (PCM). REFER to POWERTRAIN CONTROL MODULE (PCM) .
      • No:  The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.
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