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Pinpoint Test

NOTE: Make sure battery voltage is greater than 12.2 volts prior to and during this pinpoint test.
NOTE: Do not have a battery charger attached during vehicle testing.
  1. CHECK BATTERY CONDITION
    1. REFER to DIAGNOSTIC ROUTINE A  to determine if the battery can hold a charge and is OK for use.
      • Does the battery pass the condition test? 
      • Yes:  GO to step 2 .
      • No:  INSTALL a new battery. REFER to BATTERY .
  2. RETRIEVE Diagnostic Trouble Codes (DTCs)
    1. Using a scan tool, perform POWERTRAIN CONTROL MODULE (PCM)  self test.
      • Is Diagnostic Trouble Code (DTC) P0620, P0625, P0626 or P065B present? 
  3. MONITOR THE GENERATOR VOLTAGE DESIRED (GENVDSD) Parameter Identification (PID)
    1. Start the engine.
    2. Using a scan tool, view the Powertrain Control Module (PCM) Parameter Identifications (PIDs).
    3. Monitor the Powertrain Control Module (PCM) Parameter Identification (PID) GENVDSD.
      • Does the Parameter Identification (PID) indicate 15.1 volts or less? 
      • Yes:  GO to step 4 .
      • No:  GO to step  12 .
  4. COMPARE THE GENERATOR VOLTAGE DESIRED (GENVDSD) Parameter Identification (PID) WITH BATTERY VOLTAGE
    1. With the engine still running at idle, measure and record battery voltage at the battery.
    2. Using a scan tool, view the Powertrain Control Module (PCM) Parameter Identifications (PIDs).
    3. Monitor the Powertrain Control Module (PCM) Parameter Identification (PID) GENVDSD.
      • Is battery voltage within ±0.5 volt of the Parameter Identification (PID)? 
      • Yes:  The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.
      • No:  GO to step 5 .
  5. MEASURE THE "A" SENSE VOLTAGE
    1. Ignition OFF.
    2. Disconnect: Generator C102A.
    3. Ignition ON.
    4. Measure and record battery voltage at the battery.
    5. Measure:
      Fig 1: Checking Battery Condition
      G07428550Courtesy of FORD MOTOR CO.
      • Is the "A" sense voltage equal to the recorded battery voltage? 
      • Yes:  GO to step 6 .
      • 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.
  6. "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 cannot be loaded correctly using an Light-emitting Diode (LED)-style test lamp.
    1. Measure:
      Fig 2: Checking Generator Circuit Short To Ground
      G07428551Courtesy of FORD MOTOR CO.
      • Does the test lamp illuminate? 
      • Yes:  GO to step 7 .
      • No:  REPAIR the circuit.
  7. CHECK THE VOLTAGE DROP IN THE VEHICLE GROUNDS
    1. With the engine still running at idle, headlamps on and blower on high, measure:
      Fig 3: Checking Voltage Drop In Vehicle Grounds
      G07428552Courtesy of FORD MOTOR CO.
      • Is the voltage drop less than 0.5 volt? 
      • Yes:  GO to step 8 .
      • No:  INSPECT and REPAIR the engine ground, generator ground or the battery ground for corrosion.
  8. CHECK THE GENERATOR OUTPUT
    1. Connect: Generator C102A.
    2. Start the engine.
    3. Increase engine Revolutions Per Minute (RPM) until generator starts to generate output.
    4. With the engine running, measure and record battery voltage at the battery.
      • Is the voltage above 15.2 volts? 
  9. MONITOR THE GENERATOR COMMAND (GENCMD), GENERATOR MONITOR (GENMON) AND GENERATOR VOLTAGE DESIRED (GENVDSD) Parameter Identifications (PIDs)
    1. Ignition OFF.
    2. Disconnect: Generator C102A.
    3. Connect a fused jumper wire:
      Fig 4: Checking Generator Output
      G07428553Courtesy of FORD MOTOR CO.
    4. Start the engine.
    5. Using a scan tool, view the Powertrain Control Module (PCM) Parameter Identifications (PIDs).
    6. Using the active command, set the Parameter Identification (PID) GENVDSD to 14 volts.
    7. Monitor the Powertrain Control Module (PCM) Parameter Identifications (PIDs) GENMON and GENVDSD.
      • Do the Parameter Identifications (PIDs) read within 5% of each other? 
      • Yes:  GO to step 10 .
      • No:  GO to step  12 .
  10. COMPARE THE SUPPLY VOLTAGE (VPWR) Parameter Identification (PID) TO BATTERY VOLTAGE
    1. With the engine still running at idle, measure and record the battery voltage at the battery.
    2. Monitor the Powertrain Control Module (PCM) Parameter Identification (PID) VPWR.
      • Does the Parameter Identification (PID) accurately display battery voltage within ±0.5 volt of the recorded battery voltage? 
  11. CHECK Powertrain Control Module (PCM) SUPPLY VOLTAGE CIRCUITS
    1. Ignition OFF.
    2. Remove the fused jumper wire.
    3. Remove Battery Junction Box (BJB) fuse 69 (15A).
    4. Disconnect: Powertrain Control Module (PCM) C175B.
    5. Measure:
      Fig 5: Checking Powertrain Control Module (PCM) Supply Voltage Circuits
      G07428554Courtesy of FORD MOTOR CO.
      • Are the resistances less than 0.5 ohm? 
      • Yes:  GO to step 12 .
      • No:  REPAIR the affected circuit(s).
  12. 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. Reinstall Battery Junction Box (BJB) fuse 69 (15A).
    5. Reconnect the Powertrain Control Module (PCM) and generator connectors. Make sure they seat and latch correctly.
    6. 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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