U0100
Lost Communication with ECM/PCM
1992-1996 BMW 318is E36 1.8L I4 🇩🇪
Critical SeverityNetwork
Description
The diagnostic system cannot communicate with the Engine Control Module.
Symptoms
- Multiple warning lights
- Engine may not start
- Many systems inoperative
- Cannot read engine codes
Common Causes
- PCM power or ground failure
- CAN bus wiring issue
- PCM failure
- Fuse blown
- Wiring harness damage
Diagnostic Steps
- Check PCM fuses
- Test PCM power and ground circuits
- Check CAN bus wiring to PCM
- Try communicating with other modules
- Inspect wiring harness
Repair Notes
Check fuses and power supply to PCM first. CAN bus issue is second most common.
Related Codes
Other Network Codes
- U0001High Speed CAN Communication Bus
- U0002High Speed CAN Communication Bus Performance
- U0003High Speed CAN Communication Bus (+) Open
- U0004High Speed CAN Communication Bus (+) Low
- U0005High Speed CAN Communication Bus (+) High
- U0006High Speed CAN Communication Bus (-) Open
- U0007High Speed CAN Communication Bus (-) Low
- U0008High Speed CAN Communication Bus (-) High
- U0009High Speed CAN Communication Bus Shorted Together
- U0010Medium Speed CAN Communication Bus
U0100 on Other Vehicles
Common Questions
What does code U0100 mean on a 1992-1996 BMW 318is E36?
U0100 stands for "Lost Communication with ECM/PCM". The diagnostic system cannot communicate with the Engine Control Module.
What are the symptoms of U0100 on a BMW 318is E36?
Common symptoms of U0100 include: Multiple warning lights, Engine may not start, Many systems inoperative, Cannot read engine codes.
What causes U0100 on a 1992-1996 BMW 318is E36?
Common causes of U0100 include: PCM power or ground failure, CAN bus wiring issue, PCM failure, Fuse blown, Wiring harness damage.