Network
generic / SAE
U0409
Invalid Data Received from Vehicle Security Control Module
The vehicle security / alarm controller is sending implausible status data (e.g. armed/unarmed jitter). Alarm and immobilizer behaviour can become unpredictable.
SystemNetwork
Typegeneric / SAE
GroupU0
Range / number4 / 09
Possible causes
- Security module internally failed medium
- Gateway module routing CAN messages incorrectly low
- CAN terminating resistor (120 Ω) drifted out of spec low
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Inspection / repair
- Difficulty: hard
- DIY: shop recommended
- Estimated cost: 120–800 €
- Estimated time: 0.5–3 h
- Component: vehicle security module
Sources
References
sae:J2012