OBD Guide

P1601

Serial Communication Malfunction

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$6–56 (est.)

Symptoms

  • Check Engine Light Is On
  • Incorrect operation of some vehicle systems
  • Problems starting the engine
  • Dashboard malfunctions
  • Lost connection with diagnostic equipment

Causes

  • Broken or damaged serial bus wires
  • Short circuit in communication circuit
  • Oxidized or damaged connectors
  • Malfunction of one of the ECU modules
  • Problems with power supply to communication modules

How to Fix

  1. Check the condition of the serial bus wiring harness
  2. Inspect and clean all connectors in the communication circuit
  3. Check power and ground of communication modules
  4. Diagnose each system module for faults
  5. If necessary, replace damaged wires or connectors

Related codes

Error P1601 by Vehicle Brand