P0600 means Serial Communication Link. A control module has detected a fault in its internal or external serial communication with another module. It is a generic OBD-II code, so the definition is the same on any make, but the most likely cause varies by engine; confirm with a scan tool and the service information for your vehicle before buying parts.
What P0600 means
Modern vehicles have many control modules that share information over a network, usually called the CAN bus. Codes starting with U mean a module has stopped hearing another one, and voltage and processor codes mean a module is not getting clean power or has an internal fault. Low battery voltage, poor grounds, blown fuses and damaged wiring cause many of these codes, so test the battery and charging system first.
P0600 symptoms
- Check engine light
- Other warning lights or limp mode
- Intermittent stalling or electrical faults on some vehicles
Common causes of P0600
- Network wiring fault
- Poor power or ground to a module
- Failing control module
- Low battery voltage
How to diagnose P0600
- Check battery voltage and grounds
- Read codes from all modules for network faults
- Inspect network wiring and connectors
Can you drive with P0600?
It depends on the symptoms; have it checked if other warning lights come on.
P0600 tips
Communication faults often follow battery work, jump-starts or water intrusion into connectors; check power and grounds to every module first.
Will P0600 clear itself?
If the fault stops, the computer turns off the check engine light by itself after several drive cycles without seeing it again, and the code stays in memory as history for a while. Clearing P0600 with a scan tool after a repair is fine, but if the cause is still there the code returns, sometimes within one drive. Disconnecting the battery also clears codes on most vehicles, but it erases learned fuel trims and idle settings as well.
Related codes
| Code | Meaning |
|---|---|
| U0100 | Lost Communication With ECM/PCM A |
| U0101 | Lost Communication With TCM |
| P0606 | Control Module Processor |
Guides that help
When it is more than a sensor
Voltage and network codes come from wiring, the battery, the charging system or a module, not from engine or transmission wear. If a lost-communication code has left the transmission in limp mode, rule out the module and wiring before deciding the unit has failed, and see our transmissions only if testing confirms internal damage.
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