Pinpoint Test F : DTC P0625, P0626
- F1 PERFORM INSPECTION AND VERIFICATION
- Perform Inspection and Verification procedure in this information.
Was an obvious cause for an observed or reported concern found?
Yes CORRECT the cause as necessary. No GO to F2 - F2 CHECK THE GENERATOR CONNECTIONS
- Ignition OFF.
- Disconnect Generator C102A.
- Disconnect Generator C102B.
- Inspect for:
- 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
- Reconnect the generator connectors. Make sure they seat and latch correctly.
- Measure:
Positive Lead Measurement / Action Negative Lead Refer to C102B-1 Ground
Is the voltage within 0.5 volt of the recorded battery voltage?
Yes GO to F3 No TIGHTEN or INSTALL a new generator B+ nut as needed. REFER to: Generator - 6.7L Power Stroke Diesel . VERIFY high current BJB fuse 2 (275A) is OK. If OK, REPAIR the circuit. If not OK, REFER to OEM Electrical Wiring Diagram Introduction to identify the possible causes of the circuit short. - F3 CHECK THE VOLTAGE DROP IN THE GENERATOR B+ CIRCUIT
- Start the engine.
- With the engine running at idle, headlamps on and blower on high, measure:
Positive Lead Measurement / Action Negative Lead Refer to C102B-1
- Perform a wiggle test of the generator wiring and connections while measuring voltage drop.
Is the voltage drop less than 0.5 volt?
Yes For DTC P0625, GO to F4 For DTC P0626, GO to F5 No INSPECT and REPAIR any corrosion in the generator B+ circuit and positive battery cable connections. - F4 "A" SENSE CIRCUIT LOAD TESTNOTE: 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 information. 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 LED-style test lamp.
- Ignition OFF.
- Disconnect Generator C102A.
- Ignition ON.
- Install a test lamp between:
Positive Lead Measurement / Action Negative Lead Refer to C102A-3 Ground
- Perform a wiggle test on the generator wiring and measure:
Positive Lead Measurement / Action Negative Lead Refer to C102A-3 Ground
Is the "A" sense voltage within +/-0.5 volt of the recorded battery voltage?
Yes GO to F5 No VERIFY the high current BJB fuse 2 (275A) is OK. If OK, REPAIR the circuit. If not OK, REFER to OEM Electrical Wiring Diagram Introduction to identify the possible causes of the circuit short. - F5 CHECK THE GENERATOR MONITOR CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect PCM C1232B.
- Ignition ON.
- Perform a wiggle test on the generator wiring and measure:
Positive Lead Measurement / Action Negative Lead Refer to C102A-1 Ground
Is any voltage present?
Yes REPAIR the circuit. No GO to F6 - F6 CHECK THE GENERATOR MONITOR CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Perform a wiggle test on the generator wiring and measure:
Positive Lead Measurement / Action Negative Lead Refer to C102A-1 Ground
Is the resistance greater than 10, 000 ohms?
Yes GO to F7 No REPAIR the circuit. - F7 CHECK THE GENERATOR MONITOR CIRCUIT FOR AN OPEN
- Perform a wiggle test on the generator wiring and measure:
Positive Lead Measurement / Action Negative Lead Refer to C1232B-14 Refer to C102A-1
Is the resistance less than 3 ohms?
Yes GO to F8 No REPAIR the circuit. - Perform a wiggle test on the generator wiring and measure:
- F8 CHECK THE GENERATOR B+ INTERNAL RESISTANCE
- Disconnect Generator C102A.
- Disconnect Generator C102B.
Is the resistance greater than 25K ohms?
Yes GO to F9 No INSTALL a new generator. REFER to: Generator - 6.7L Power Stroke Diesel . - F9 CHECK THE RESISTANCE OF THE VOLTAGE REGULATOR INTERNAL CIRCUITS
- Measure:
Positive Lead Measurement / Action Negative Lead Generator pin 1 (Component Side) Generator case Generator pin 2 (Component Side) Generator case Generator pin 3 (Component Side) Generator case
Are the resistances greater than 10, 000 ohms?
Yes GO to F10 No INSTALL a new generator. REFER to: Generator - 6.7L Power Stroke Diesel . - Measure:
- F10 COMPARE THE GENMON PID (PARAMETER IDENTIFICATION) AND THE GENCMD PID (PARAMETER IDENTIFICATION)
- Connect PCM C1232B.
- Connect a fused jumper wire:
Positive Lead Measurement / Action Negative Lead Refer to C102A-1 Refer to C102A-2
- Start the engine.
- Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
- Using the active command, set the PID GENVDSD to 14 volts.
- Monitor the PCM Parameter Identifications (PIDs) GENMON and GENCMD.
- Perform a wiggle test of the generator wiring and connections.
Do the Parameter Identifications (PIDs) read within 5% of each other for the first 3-5 seconds?
Yes REMOVE the fused jumper wire. INSTALL a new generator. REFER to: Generator - 6.7L Power Stroke Diesel . No REMOVE the fused jumper wire. GO to F11 - F11 CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION
- Ignition OFF.
- Disconnect and inspect all PCM connectors.
- 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
- Connect all connectors. Make sure they seat and latch correctly.
- Operate the system and determine if the concern is still present.
Is the concern still present?
Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW the TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, Refer to PCM GUIDED ROUTINE TESTING 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.