P0600
Serial Communication Link
Computer / communication
Generic OBD-II
High
What it means
P0600 means the ECM has lost internal serial communication with another controller on the vehicle's data bus. Because modules constantly share sensor and control data, this can set off several unrelated warning lights and, in some cases, cause limp mode, stalling, or a no-start. Damaged bus wiring, bad grounds, and low battery voltage are the usual causes.
High
Can I keep driving? Risky — a broken data link can trigger limp mode, multiple warning lights, or even a no-start; have it diagnosed before relying on the vehicle.
Common symptoms
What you'll notice
- Check-engine light plus several other warning lights
- Erratic behaviour of systems that depend on module-to-module data
- Possible no-start, stall, or reduced-power limp mode
- A scan tool can't reach one or more modules
Common causes
Most likely first
- Damaged or corroded data-bus (CAN) wiring or connectorsLikely
- Poor grounds or low battery voltage upsetting the busCommon
- A failing control module pulling the bus downCommon
- Internal ECM faultLess often
How to diagnose & fix
Work through it in order
- Check battery voltage and the main ground connections first.
- Scan all modules and note which ones are unreachable to narrow the fault down.
- Inspect the bus wiring and connectors between the ECM and the missing module.
- Back-probe the bus circuits for opens or shorts.
- Repair the wiring, then reprogram or replace the faulty module or ECM as a last resort.
FAQ
Quick answers
Is it safe to drive with P0600?+
Not reliably — lost communication between modules can cause limp mode, stalling, or a no-start without warning. Get it diagnosed before depending on the car.
Can I just clear P0600?+
You can, but it usually returns immediately or on the next start because the underlying wiring, ground, or module fault is still present.
Related codes
Often seen with P0600
Read & clear P0600 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX