Pinpoint Test BP : U0647
- Normal Operation and Fault Conditions
REFER to: Electric Powertrain Control - System Operation and Component Description .
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition SOBDMC U0647:00 Lost Communication with Motor Electronics Coolant Pump "B": No Sub Type Information This DTC sets when messages are missing from the Motor Electronics Coolant Pump "B". Possible Sources
- Communications network concern
- Motor Electronics Coolant Pump "B"
- BP1 CARRY OUT A VEHICLE INSPECTION AND VERIFY THE SELF-TEST PROCEDURENOTE: If the self-test or communication concern occurred after a failed or aborted reprogram, the module may be blank. Attempt to reprogram the module again before continuing with this pinpoint test.
- Visually inspect the following for obvious signs of electrical damage:
- harness wiring
- electrical connections
- Verify the correct procedure was used to activate the self-test for the scan tool. Refer to SCAN TOOL SETUP AND FUNCTIONALITY .
Was the correct self-test procedure used?
Yes GO to BP2 No Refer to SCAN TOOL SETUP AND FUNCTIONALITY . - Visually inspect the following for obvious signs of electrical damage:
- BP2 CARRY OUT THE NETWORK TEST
- Note:
When using FDRS, the scan tool attempts to communicate with the PCM first. After establishing communication with the PCM, the scan tool then attempts to communicate with all modules on the vehicle. If an FDRS session cannot be established, FDRS may state no communication can be established with the PCM:
- Choose No when the scan tool prompts whether or not to retry communication.
- Enter a PCM part number, tear tag or calibration number to identify the vehicle and start a session. The PCM part number and 4- character tear tag are located on the PCM.
- Ignition ON.
Do all modules indicate pass?
Yes GO to BP3 No GO to BP4 - Note:
When using FDRS, the scan tool attempts to communicate with the PCM first. After establishing communication with the PCM, the scan tool then attempts to communicate with all modules on the vehicle. If an FDRS session cannot be established, FDRS may state no communication can be established with the PCM:
- BP3 CHECK FOR A MOTOR ELECTRONICS COOLANT PUMP "B" CONCERN
- Using a diagnostic scan tool, perform the Inverter System Controller (ISC) self-test.
- Check for any other Motor Electronics Coolant Pump "B" related symptoms.
Is a concern present?
Yes DIAGNOSE the Motor Electronics Coolant Pump "B" concern. REFER to: Electric Powertrain Cooling . 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. - BP4 INVERTER SYSTEM CONTROLLER (ISC) SELF-TEST
- Confirm the Inverter System Controller (ISC) was the only module to fail.
Was the Inverter System Controller (ISC) the only module to fail?
Yes GO to BP5 No DIAGNOSE the network concern. REFER to: Communications Network . - BP5 CHECK THE INVERTER SYSTEM CONTROLLER (ISC) B+ CIRCUIT FOR VOLTAGE
- Ignition OFF.
- Disconnect Inverter System Controller (ISC) C1458A.
- Ignition ON.
Is the voltage greater than 10.5 volts?
Yes GO to BP6 No REPAIR the circuit. - BP6 CHECK THE INVERTER SYSTEM CONTROLLER (ISC) VPWR CIRCUITS FOR VOLTAGE
- Ignition OFF.
- Connect a 5A fused jumper between:
Positive Lead Measurement / Action Negative Lead C1458A-K3 Ground
- Ignition ON.
- Measure and record:
Positive Lead Measurement / Action Negative Lead C1458A-L2 Ground C1458A-M2 Ground
Are the voltages greater than 10.5 volts?
Yes GO to BP7 No REPAIR the circuit. - BP7 CHECK THE INVERTER SYSTEM CONTROLLER (ISC) GROUND CIRCUITS FOR AN OPEN
- Ignition OFF.
- Measure and record:
Positive Lead Measurement / Action Negative Lead C1458A-L4 Ground C1458A-M4 Ground
Are the resistances less than 5 ohms?
Yes DIAGNOSE the network concern. REFER to: Communications Network . No REPAIR the open circuit.