Code result
U3004
Accessory Power Relay
Moderate severity
What it means
Fault on the accessory power relay that switches power to comfort/accessory loads (radio, infotainment, etc.) when the key is in ACC position.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Relay contacts failed or coil open
highOne of the most commonly reported causes for this code — check this first.
Gateway module routing CAN messages incorrectly
lowLess common, but worth ruling out after the more likely causes.
CAN terminating resistor (120 Ω) drifted out of spec
lowLess common, but worth ruling out after the more likely causes.
Related help
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