P1803

Symptoms

• Engine won't start
• The engine stalls immediately after starting
• The immobilizer indicator is flashing
• No response when turning the key
• Immobilizer error message on dashboard

Causes

• Malfunction of the immobilizer control unit
• Damage to the key reader antenna
• Dead battery in the ignition key
• Damage to the transponder chip in the key
• Problems with system wiring or connectors

How to Fix

1. Check the battery in the ignition key
2. Diagnose the immobilizer control unit
3. Check the integrity of the reader antenna
4. Check the condition of the wiring and connectors
5. Reprogram keys or control unit
6. Repair only from an authorized dealer

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