P0601

What does P0601 mean?

P-code P0601 means "Serial Communication Link Malfunction". It is a generic OBD-II diagnostic trouble code (DTC) in the powertrain. A communication failure has been detected — the module responsible for the serial communication link malfunction is not responding on the vehicle network. This warning should be addressed within the next few days to avoid further damage. This code applies to OBD-II compliant electric and hybrid vehicles.

Possible Causes

• CAN bus wiring fault (short, open, or termination resistor failure)
• Faulty control module not transmitting on the vehicle network
• Power supply issue preventing the module from initializing
• Software mismatch or corruption in the affected module

Recommended Actions

1. 1 Avoid aggressive driving and schedule a diagnostic appointment within the next 1–3 days
2. 2 Scan for all DTCs with an OBD-II scanner — note any related codes stored alongside P0601
3. 3 Check CAN bus wiring for damage; verify termination resistance (should be ~120 Ω between CAN-H and CAN-L)
4. 4 Verify power supply and ground connections at the affected module
5. 5 Clear the DTC, road-test the vehicle, and re-scan to confirm whether the fault returns
6. 6 If the fault persists after inspection and clearing, consult an EV-certified technician for component replacement

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