What Does U1797 Mean?
The door lock control module is not acknowledging network messages. The system cannot verify that door lock/unlock commands are being received by the appropriate module.
Common Causes
35%
Failed door module or door lock control module
30%
Broken or damaged wiring in door harness, especially at flex points
20%
Corroded or water-damaged door module connector
10%
Body control module or central locking system communication failure
5%
SCP network fault affecting door and accessory modules
Diagnostic Steps
1
Step 1: Verify power and ground to door lock module at connector terminals
2
Step 2: Inspect door wiring harness at hinge area for breaks (open and close door while monitoring continuity)
3
Step 3: Remove door panel and check module connector for water damage, corrosion, or pin issues
4
Step 4: Use scan tool to attempt lock/unlock commands and verify if door module acknowledges or responds
5
Step 5: Test SCP network signals at door module to confirm proper communication bus operation
Estimated Repair Cost
$120 - $600
Parts + labor, varies by vehicle and location
The door lock control module is not acknowledging network messages. The system cannot verify that door lock/unlock commands are being received by the appropriate module.
The most common cause of U1797 (SCP (J1850) Lack of Acknowledgment for Door Locks) is: Failed door module or door lock control module
Typical repair costs for U1797 range from $120 to $600, depending on the vehicle, location, and whether you do it yourself or go to a shop.
May prevent proper locking/unlocking of doors, compromising vehicle security. In some cases, may prevent remote entry or leave doors unexpectedly unlocked.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to U1797 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Network
System
Door Lock / Security System
Difficulty
Type
Manufacturer
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
