DTC P1645: ID Code Communication Error: Troubleshooting

2013 Suzuki SX4 Crossover, Automatic CVT TransSECTION Troubleshooting
P1645: TROUBLESHOOTING CHART

Step Action YES NO
Was "Immobilizer Control System Check" performed?  Go to Step 2. Go to IMMOBILIZER CONTROL SYSTEM CHECK .
DTC check of ECM 
  1. Check ECM for DTC referring to DTC CHECK .

Is DTC U0073, U0101, U0121, U0140 and/or U0155 detected? 
Go to applicable DTC troubleshooting. Go to Step 3.
CAN communication circuit check 
  1. Disconnect connectors of all control modules communicating by means of CAN.
  2. Check CAN communication circuit between control modules for open, short and high resistance.

Is each CAN communication circuit in good condition? 
Replace ID controller with new one. If DTC P1645 is still detected, substitute a known-good ECM and recheck. Repair circuit.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.