What Does U3005 Mean?
DTC U3005 indicates that a control module has detected a fault in the Retained Accessory Power (RAP) system. RAP allows certain accessories (radio, power windows, power seats) to remain operational for a calibrated period (typically 10-20 minutes) after the ignition is turned off, until a door is opened. This code sets when the RAP timer, relay control, or power feed circuit does not function as expected.
Common Causes
35%
Body Control Module RAP logic fault — BCM not properly managing the RAP timer or relay driver output
25%
RAP relay failure or accessory power relay not holding in the retained power state after ignition off
20%
Door ajar switch circuit malfunction causing premature RAP cancellation or failure to cancel
20%
Ignition switch position signal fault preventing the BCM from detecting proper key-off transition to initiate RAP
Diagnostic Steps
1
Step 1: Verify RAP operation — turn the ignition off without opening the door and check if the radio and power windows remain functional for at least 10 minutes; note whether RAP activates at all or cuts out prematurely.
2
Step 2: Check door ajar switch signals on the scan tool — open and close each door and verify the BCM registers the correct door status; a stuck-closed (always showing closed) signal could prevent RAP cancellation, while stuck-open could prevent RAP activation.
3
Step 3: Monitor the ignition switch position input at the BCM on the scan tool — cycle through Off, Accessory, Run, and Start positions and verify the BCM reads each position correctly.
4
Step 4: Test the RAP relay — locate it in the relay box, swap with an identical relay, or bench-test the relay coil (typical resistance 60-100 ohms) and contact operation with a 12V supply.
5
Step 5: If all inputs and relay test correctly, attempt a BCM software update — if the issue persists, the BCM's internal RAP control circuitry may need replacement.
Estimated Repair Cost
$30 - $500
Parts + labor, varies by vehicle and location
DTC U3005 indicates that a control module has detected a fault in the Retained Accessory Power (RAP) system. RAP allows certain accessories (radio, power windows, power seats) to remain operational for a calibrated period (typically 10-20 minutes) after the ignition is turned off, until a door is op...
The most common cause of U3005 (Retained Accessory Power) is: Body Control Module RAP logic fault — BCM not properly managing the RAP timer or relay driver output
Typical repair costs for U3005 range from $30 to $500, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Safe to drive. RAP failure only affects convenience features after the ignition is turned off. However, if the RAP system fails in the on state (stuck providing power), it could drain the battery overnight.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to U3005 to identify the root cause.
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Quick Info
Category
Network
System
Electrical System / Retained Accessory Power
Difficulty
Type
Generic (SAE)
Recommended Tools
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