Code
U0145
Generic
U — Network/User
Lost Communication With Body Control Module E
Views:
UK: 13
EN: 19
RU: 13
AI status
Completed
Completed
100%
Causes
- BCM E internal failure
- Loss of BCM power or ground (blown fuse, poor ground, open/short)
- Damaged or corroded BCM connector or pins
- Open, shorted or crossed CAN / data-bus wiring
- Bus driven to a dominant state by another module (bus-off condition)
- Aftermarket accessories or recent repairs that disturbed the network
Symptoms
- Warning message(s) on cluster: “No Communication With BCM” or similar
- Loss or erratic operation of body functions (door locks, lights, wipers, interior lights, keyless entry)
- Security/immobilizer or remote functions not working
- Multiple network-related DTCs present
- Possible battery drain if BCM stuck in an abnormal state
What to check
- Connect a professional scan tool and confirm U0145 is current or historic; capture freeze frame and related network codes
- Check battery voltage and charging system condition
- Inspect fuses/relay for BCM power and accessory feeds
- Visually inspect BCM connector for corrosion, bent pins, water intrusion
- Verify proper ground(s) at BCM with low-resistance test
- Measure CAN_H and CAN_L voltages at BCM connector with ignition on
Signal parameters
- CAN recessive voltage: both CAN_H and CAN_L roughly 2.5 V (each) at idle
- CAN dominant voltages: CAN_H ≈ 3.5 V, CAN_L ≈ 1.5 V during dominant bits
- Typical bus baud rates: 125 kbps, 250 kbps, 500 kbps or 1 Mbps (vehicle-specific)
- BCM heartbeat/keepalive message: periodic broadcast (comm interval commonly 100–1000 ms; exact ID/manufacturer-specific)
- Expected low RX/TX error counters; high CRC/frame error counts or bus-off state indicate network faults
Diagnostic algorithm
- Use a scan tool to attempt communication with BCM E and note related codes/time stamps.
- Check battery voltage (should be >12.4 V at rest) and verify charging system. Low voltage can corrupt communications.
- Inspect BCM power/ground fuses and relays; verify fused feeds are present at BCM pins with ignition ON and OFF as required.
- Visually inspect the BCM connector for damage, corrosion, bent pins or water intrusion; repair connector issues before further diagnosis.
- With ignition ON, measure DC voltage at BCM power and ground terminals and verify within factory spec (usually battery voltage at power pin, near 0 Ω to chassis at ground).
- Measure CAN_H and CAN_L at the BCM connector and at another known-good node. Compare readings. Look for recessive ~2.5 V on both lines and correct dominant voltages when active.
- Use an oscilloscope or CAN bus analyzer to observe message traffic and error frames. Look for bus-off state, repeated dominant bits, or one line shorted to voltage/ground.
- If one module is causing the bus fault, disconnect suspected modules (starting with aftermarket devices) one at a time and re-check bus behavior and communication.
- If wiring and power/ground are good but no comms, try re-initializing or reflashing BCM software per manufacturer procedures; confirm correct part number and calibration.
- If BCM is confirmed failed after elimination of wiring/power and other modules, replace BCM and program/configure with OEM tool. Clear codes and retest all body functions and network health.
- After repair, road test and re-scan to ensure code does not return and that no related network codes are present.
Likely causes
- Loose/poor ground or fused power to the BCM
- Short to ground or battery on CAN_H or CAN_L at or near BCM
- Failed BCM (intermittent or permanent)
- Other module on same bus causing bus-off or heavy errors
- Connector corrosion or bent pins at BCM
Fault status
Status
U0145 - Lost Communication With Body Control Module E: BCM E not responding on data bus. Check BCM power/ground, connector, and CAN bus for faults.
Repair difficulty: Medium
Diagnostic time: 1.0-3.0 hours
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email
Code
U0145
HYUNDAI
U — Network/User
Lost Communication With Body Control Module “E”
Views:
UK: 13
EN: 13
RU: 17
AI status
Completed
Completed
100%
Causes
- BCM E internal failure
- Loss of BCM power or ground (blown fuse, poor ground, open/short)
- Damaged or corroded BCM connector or pins
- Open, shorted or crossed CAN / data-bus wiring
- Bus driven to a dominant state by another module (bus-off condition)
- Aftermarket accessories or recent repairs that disturbed the network
Symptoms
- Warning message(s) on cluster: “No Communication With BCM” or similar
- Loss or erratic operation of body functions (door locks, lights, wipers, interior lights, keyless entry)
- Security/immobilizer or remote functions not working
- Multiple network-related DTCs present
- Possible battery drain if BCM stuck in an abnormal state
What to check
- Connect a professional scan tool and confirm U0145 is current or historic; capture freeze frame and related network codes
- Check battery voltage and charging system condition
- Inspect fuses/relay for BCM power and accessory feeds
- Visually inspect BCM connector for corrosion, bent pins, water intrusion
- Verify proper ground(s) at BCM with low-resistance test
- Measure CAN_H and CAN_L voltages at BCM connector with ignition on
Signal parameters
- CAN recessive voltage: both CAN_H and CAN_L roughly 2.5 V (each) at idle
- CAN dominant voltages: CAN_H ≈ 3.5 V, CAN_L ≈ 1.5 V during dominant bits
- Typical bus baud rates: 125 kbps, 250 kbps, 500 kbps or 1 Mbps (vehicle-specific)
- BCM heartbeat/keepalive message: periodic broadcast (comm interval commonly 100–1000 ms; exact ID/manufacturer-specific)
- Expected low RX/TX error counters; high CRC/frame error counts or bus-off state indicate network faults
Diagnostic algorithm
- Use a scan tool to attempt communication with BCM E and note related codes/time stamps.
- Check battery voltage (should be >12.4 V at rest) and verify charging system. Low voltage can corrupt communications.
- Inspect BCM power/ground fuses and relays; verify fused feeds are present at BCM pins with ignition ON and OFF as required.
- Visually inspect the BCM connector for damage, corrosion, bent pins or water intrusion; repair connector issues before further diagnosis.
- With ignition ON, measure DC voltage at BCM power and ground terminals and verify within factory spec (usually battery voltage at power pin, near 0 Ω to chassis at ground).
- Measure CAN_H and CAN_L at the BCM connector and at another known-good node. Compare readings. Look for recessive ~2.5 V on both lines and correct dominant voltages when active.
- Use an oscilloscope or CAN bus analyzer to observe message traffic and error frames. Look for bus-off state, repeated dominant bits, or one line shorted to voltage/ground.
- If one module is causing the bus fault, disconnect suspected modules (starting with aftermarket devices) one at a time and re-check bus behavior and communication.
- If wiring and power/ground are good but no comms, try re-initializing or reflashing BCM software per manufacturer procedures; confirm correct part number and calibration.
- If BCM is confirmed failed after elimination of wiring/power and other modules, replace BCM and program/configure with OEM tool. Clear codes and retest all body functions and network health.
- After repair, road test and re-scan to ensure code does not return and that no related network codes are present.
Likely causes
- Loose/poor ground or fused power to the BCM
- Short to ground or battery on CAN_H or CAN_L at or near BCM
- Failed BCM (intermittent or permanent)
- Other module on same bus causing bus-off or heavy errors
- Connector corrosion or bent pins at BCM
Fault status
Status
U0145 - Lost Communication With Body Control Module E: BCM E not responding on data bus. Check BCM power/ground, connector, and CAN bus for faults.
Repair difficulty: Medium
Diagnostic time: 1.0-3.0 hours
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email