LEMON Manuals: Even more car manuals for everyone
Home >> Mercury >> 2009 >> Mariner Base, 2.5 7, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 105 (Charging System - General Information) >> Diagnostic Tests >> Charging System >> Pinpoint Tests >> Pinpoint Test B: The Charging System Warning Indicator is On and Any Charging System DTC Stored

Pinpoint Test B: The Charging System Warning Indicator is On and Any Charging System DTC Stored

WARNING: This page is about a different car, the 2009 Mercury Grand Marquis and 2009 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.

Refer to appropriate SYSTEM WIRING DIAGRAMS article, Charging System for schematic and connector information.

Normal Operation 

With the engine running, the charging system warning indicator is off. The Sense A circuit 35 (OG/LB) to the generator field coil is 13-15 volts. This voltage feedback is used by the regulator to maintain the battery voltage at the desired setpoint. The S (stator) circuit (internal to the generator) is used to monitor generator operation. This circuit and other regulator internal conditions are checked by the regulator to allow the PCM to turn off the charging system warning indicator by sending a message over the controller area network (CAN) bus to the instrument cluster (IC). The positive battery output (B+) circuit 38 (RD) is the generator output voltage supplied to the battery and electrical system.

This pinpoint test is intended to diagnose the following:

PINPOINT TEST B: THE CHARGING SYSTEM WARNING INDICATOR IS ON AND ANY CHARGING SYSTEM DTC STORED 

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. B1 CONFIRM THE BATTERY CONDITION 
    1. YES  : Go to  B2.
    2. NO  : CORRECT the battery condition and Go to  B2.
  2. B2 CHECK THE BATTERY JUNCTION BOX (BJB) FUSE F6 (15A) 
    • Check fuse: BJB F6 (15A)
    • Is BJB F6 (15A) OK? 
    1. YES  : Go to  B3.
    2. NO  : REPAIR circuit 35 (OG/LB) and INSTALL a fuse. INSPECT PCM and engine ground circuits and make sure they are securely attached. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  3. B3 CHECK THE GENERATOR B+ CONNECTION 
    • Key in OFF position.
    • Inspect generator C102b, B+ circuit 38 (RD) connection. Connection should be tight.
      • Fig 1: Checking Generator B+ Circuit For Voltage
      GF0004524Courtesy of FORD MOTOR CO.
    • Measure the voltage between generator C102b, B+ circuit 38 (RD) and ground.
    • Is generator C102b connection tight and does the generator B+ measure battery voltage? 
    1. YES  : Go to  B4.
    2. NO  : TIGHTEN the generator B+ connection or REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  4. B4 MONITOR THE PCM PID GENERATOR MONITOR WITH KEY ON/ENGINE OFF (KOEO) 
    • Key in ON position.
    • Enter the following diagnostic mode on the diagnostic tool: Clear the PCM DTCs
    • Enter the following diagnostic mode on the diagnostic tool: Select PCM PIDs
      NOTE: Many of the PCM PIDs selected will be monitored later in this pinpoint test.

      Select and monitor the following PCM PIDs:

      • Generator Monitor (GENMON).
      • Generator Command Duty Cycle (GENCMD).
      • Generator Voltage Desired (GENVDSD).
      • Generator Fault Indicator Lamp (GENFIL).
      • Engine Revolutions Per Minute (RPM).
      • Module Supply Voltage (VPWR).
    • Monitor the GENMON PID.
    • Does the GENMON PID read 0%? 
    1. YES  : Go to  B5.
    2. NO  : Go to  B8.
  5. B5 MONITOR THE PCM PID GENERATOR MONITOR WITH KEY ON/ENGINE RUNNING (KOER) 
    • Key in START position.
    • With the engine at idle, wait 15 seconds for the GENVDSD PID to increase to greater than 13 volts.
    • Monitor PID GENMON at idle and 3,000 RPM.
    • Does the GENMON PID read between 3% and 98% at engine idle speed and at 3,000 RPM? 
    1. YES  : Go to  B6.
    2. NO  : Go to  B8.
  6. B6 MONITOR THE PCM PIDs GENERATOR MONITOR, MODULE SUPPLY VOLTAGE AND GENERATOR DESIRED VOLTAGE WITH THE ENGINE AT 3,000 RPM 
    • Turn all electrical accessories (lights, blower motor, etc.) off.
      • NOTE: If GENMON PID does not remain below 85%, make sure that the battery is at an acceptable state of charge and that all electrical accessories are off.
    • Increase the engine speed to 3,000 RPM (or road test).
    • Does the VPWR PID remain within ± 0.5 volt of the GENVDSD PID when the GENMON PID is less than 85%? 
    1. YES  : Go to  B7.
    2. NO  : Go to  B17.
  7. B7 MONITOR THE PCM PIDs GENERATOR MONITOR, MODULE SUPPLY VOLTAGE AND GENERATOR DESIRED VOLTAGE WITH THE ENGINE AT IDLE 
    • Return the engine speed to idle.
      • CAUTION: On vehicles with low electrical loads, it may be necessary to add external loads (devices connected to power points, etc.) to determine the maximum GENMON value. GENMON value will not read between 95%-98% on a vehicle with minimal electrical accessories. As long as there is a significant increase in the GENMON PID following the procedure below, answer YES to the question.
    • Determine the maximum GENMON PID value by lowering engine idle RPM to 500 RPM or less using output state control and turn on all electrical accessories until the VPWR PID is less than the GENVDSD PID by at least 0.7 volt. Under this condition the GENMON PID should read between 95% and 98%.
    • Does the GENMON PID read between 95% and 98%? 
    1. YES  : Go to  B19.
    2. NO  : Go to  B17.
  8. B8 CHECK THE VOLTAGE OUTPUTS FROM THE PCM 
    • Key in OFF position.
    • Disconnect: Generator C102a
    • Key in ON position.
    • Measure the voltage of the following circuits:
      EXPECTED VOLTAGES

      Generator Connector Circuit Expected Voltage (Approximate)
      C102a-1 1817 (YE) 8-11 volts (should be less than battery voltage)
      C102a-2 1816 (YE/LB) 0 volts
      C102a-3 35 (OG/LB) Battery voltage
    • Are the voltages as indicated for each circuit? 
    1. YES  : Go to  B13.
    2. NO  : If a fault is detected in the GENCOM circuit 1816 (YE/LB) or GENMON circuit 1817 (YE), go to  B9.

      If a fault is detected in the A sense 35 (OG/LB) circuit, go to  B12.

  9. B9 CHECK CIRCUITS 1816 (YE/LB) AND 1817 (YE) FOR DAMAGE OR AN OPEN 
    • Key in OFF position.
    • Disconnect: Generator C102a
    • Disconnect: PCM C175b
    • Disconnect: PCM C175e
    • Inspect the following for damaged or pushed-out pins:
      Component Connector Circuit
      PCM C175b-32 1816 (YE/LB)
      PCM C175e-5 1817 (YE)
      Generator C102a-2 1816 (YE/LB)
      Generator C102a-1 1817 (YE)
    • Measure the resistance between circuit C175b-32 and C102a-2 and circuit C175e-5 and C102a-1.
    • Are the connectors and pins free of damage and are the resistances less than 5 ohms? 
    1. YES  : Go to  B10.
    2. NO  : REPAIR the affected circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  10. B10 CHECK CIRCUITS 1816 (YE/LB) AND 1817 (YE) FOR SHORT TO VOLTAGE 
    • Key in ON position.
    • Measure the voltage between circuits C102a-1, 1817 (YE) and C102a-2, 1816 (YE/LB).
    • Are the voltages approximately 0 volt? 
    1. YES  : Go to  B11.
    2. NO  : REPAIR the affected circuits. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  11. B11 CHECK CIRCUITS 1816 (YE/LB) AND 1817 (YE) FOR SHORT TO GROUND 
    • Key in OFF position.
    • Measure the resistance between circuit C102a-1, 1817 (YE) harness side and ground and C102a-2, 1816 (YE/LB) harness side and ground and also measure resistance. between each other:
    • Are the resistances less than 5 ohms? 
    1. YES  : Go to  B24.
    2. NO  : REPAIR the affected circuits. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  12. B12 CHECK CIRCUIT 35 (OG/LB) FOR DAMAGE OR AN OPEN 
    • Key in OFF position.
    • Disconnect: Generator C102a
    • Inspect C102a-3 for damaged or pushed-out pins.
    • Measure the resistance of the circuit A sense circuit 35 (OG/LB) between the battery and C102a-3 generator connector.
    • Are the connectors and pins free of damage and are the resistances less than 5 ohms? 
    1. YES  : Go to  B24.
    2. NO  : REPAIR the affected circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  13. B13 CHECK FOR SHORTED CIRCUITS 
    • Key in OFF position.
    • Disconnect: Generator C102a
    • Verify that PID GENMON reads 100%.
    • Carry out the Wiggle Test of wiring to determine if PID GENMON changes from 100%.
    • Does PID GENMON change from 100%? 
    1. YES  : REPAIR short circuit on 1817 (YE) C102a-1.
    2. NO  : Go to  B14.
  14. B14 CHECK THE PCM PID GENERATOR MONITOR INPUT TO THE PCM 
      Fig 2: Connecting Fused Jumper Wire
      GF0016079Courtesy of FORD MOTOR CO.
    • Connect a fused (10A) jumper wire between generator C102a-1, circuit 1817 (YE), harness side and ground.
    • Key in ON position.
    • Monitor the GENMON PID while performing a wiggle test on the wire harness.
    • Does the GENMON PID read 0%? 
    1. YES  : Go to  B15.
    2. NO  : REPAIR open connection on circuit 1817 (YE). INSPECT generator C102a-1 and PCM C175e-5 for damage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  15. B15 COMPARE THE PCM PIDS GENERATOR MONITOR AND GENERATOR FIELD DUTY CYCLE 
    • Key in OFF position.
    • Disconnect: Fused (10A) Jumper Wire
      • Fig 3: Connecting Fused Jumper Wire
      GF0016080Courtesy of FORD MOTOR CO.
    • Connect a fused (10A) jumper wire between generator C102a-1, circuit 1817 (YE), harness side and generator C102a-2, circuit 1816 (YE/LB), harness side.
    • Key in ON position.
    • Monitor the GENMON and GENCMD PIDs while performing a wiggle test on the harness.
    • Does the GENMON PID read within 2% of the GENCMD PID? 
    1. YES  : Go to  B16.
    2. NO  : INSPECT C175b-10, circuit 57 (BK), PCM ground circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  16. B16 A SENSE CIRCUIT LOAD TEST 
    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.
    • Key in ON position.
    • Using a 12-volt test lamp, check for voltage at C102a-3, circuit 35 (OG/LB).
    • Does the test lamp illuminate? 
    1. YES  : Go to  B23.
    2. NO  : REPAIR connection on circuit 35 (OG/LB). INSPECT generator C102a-3 for damage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  17. B17 CHECK THE PCM VPWR PID 
      Fig 4: Checking Charging System Voltage
      GF0001354Courtesy of FORD MOTOR CO.
    • With the engine running, measure the battery voltage.
    • Monitor the VPWR PID.
    • Are the battery voltage and VPWR PID within 0.5 volt of each other? 
    1. YES  : Go to  B19.
    2. NO  : Go to  B18.
  18. B18 MEASURE THE PCM INPUT VOLTAGE 
    • Key in OFF position.
    • Disconnect: PCM C175b
    • Key in ON position.
      • Fig 5: Checking Circuit For Voltage
      GF0016081Courtesy of FORD MOTOR CO.
    • Measure the voltage between PCM input voltage pins 35, 36 and 45 to PCM ground pin 10.
    • Are voltages within 0.5 volt of PID VPWR? 
    1. YES  : Go to  B24.
    2. NO  : REPAIR high resistance or loose connections between C175b-35 circuit 361 (RD), C175b-36 circuit 361 (RD), C175b-45 circuit 729 (RD/WH) PCM power circuits or C175b-10, circuit 57 (BK), PCM ground circuit.
  19. B19 CHECK THE GENERATOR B+ RESISTANCE 
    • Key in OFF position.
    • Disconnect: Battery
    • Disconnect: Generator C102b
      • Fig 6: Checking Circuit For Short To Ground
      GF0016082Courtesy of FORD MOTOR CO.
    • Measure the resistance between generator C102b, component side and the generator housing.
    • Is the resistance greater than 125K ohms? 
    1. YES  : Go to  B20.
    2. NO  : INSTALL a new generator. REFER to GENERATOR & REGULATOR article. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  20. B20 CHECK THE RESISTANCE OF THE VOLTAGE REGULATOR INTERNAL CIRCUITS TO GROUND 
    • Measure the resistance between generator C102a, component side and ground. Refer to the following table.
      Pin Expected Resistance
      1 Greater than 1,000K ohms
      2 Greater than 125K ohms
      3 Greater than 125K ohms
    • Are the resistance values as indicated? 
    1. YES  : Go to  B21.
    2. NO  : INSTALL a new generator. REFER to GENERATOR & REGULATOR article. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  21. B21 ROAD TEST IN AN ATTEMPT TO VERIFY THE FAULT 
    • Connect: Generator C102b
    • Connect: Generator C102a
    • Connect: Battery
    • Carry out a road test and monitor the following PIDs:
      • Generator monitor (GENMON).
      • Generator voltage desired (GENVDSD).
      • Module supply voltage (VPWR).
    • Does the GENMON PID read either 0% or 100% during the road test? 
    1. YES  : Go to  B2.
    2. NO  : If a road test did not cause the fault to occur, intermittent fault condition may be present. Go to  B22.
  22. B22 USE THE VEHICLE DATA RECORDER (VDR) TO CAPTURE INTERMITTENT FAULT CONDITION 
    • Connect a VDR to the vehicle and setup to capture the following PIDs:
      • Generator monitor (GENMON).
      • Generator command duty cycle (GENCMD).
      • Generator voltage desired (GENVDSD).
      • Generator fault indicator lamp (GENFIL).
      • Engine revolutions per minute (RPM).
      • Module supply voltage (VPWR).
    • Set the VDR to trigger if any of the following events occur during vehicle operation (waiting 15 seconds after start):
      • VPWR PID reads greater than 15.2 volts.
      • GENMON PID reads 0% or 100%.
    • Road test the vehicle.
    • Was a fault captured by the VDR? 
    1. YES  : RECORD any values from the VDR that may have been captured. If no charging system DTCs are present, go to Pinpoint Test C . If any charging system DTCs are present, go to  B3.
    2. NO  : No problem found at this time. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  23. B23 CHECK THE CHARGING SYSTEM CIRCUITS FOR INTERMITTENT FAULTS 
    • Key in OFF position.
    • Connect: Generator C102b
    • Connect: Generator C102a
    • Connect: PCM C175b
    • Connect: PCM C175e
    • Connect the diagnostic tool.
    • Key in START position.
    • With the engine running, monitor the charging system warning indicator lamp and the scan tool for DTCs.
    • Does the charging system warning indicator lamp illuminate and does any charging system DTC get stored into memory? 
    1. YES  : INSTALL a new generator. REFER to GENERATOR & REGULATOR article. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
    2. NO  : The fault is not present and cannot be recreated at this time. This may indicate an intermittent fault. Go to  B19.
  24. B24 CHECK THE CHARGING SYSTEM CIRCUITS FOR INTERMITTENT FAULTS 
    • Key in OFF position.
    • Connect: Generator C102b
    • Connect: Generator C102a
    • Connect: PCM C175b
    • Connect: PCM C175e
    • Connect the diagnostic tool.
    • Key in START position.
    • With the engine running, monitor the charging system warning indicator lamp and the scan tool for DTCs.
    • Does the charging system warning indicator lamp illuminate and does any charging system DTC get stored into memory? 
    1. YES  : INSTALL a new PCM. REFER to ELECTRONIC ENGINE CONTROLS article.
    2. NO  : The fault is not present and cannot be recreated at this time. This may indicate an intermittent fault. Go to  B19.
scientia non olet · About LEMON Manuals