U1146 Code - Lost Communication With External Memory
Quick Answer
The first time the vehicle is started, the Transmission Control Module (TCM) receives hydraulic calibration data from an external EEPROM (located in the transmission) and stores this information in the EEPROM of the TCM. Common causes include Faulty Transmission Control Module (TCM), Transmission Control Module (TCM) harness is open or shorted, Transmission Control Module (TCM) circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- U1146 indicates Lost Communication With External Memory.
- Common causes
- Common causes include Faulty Transmission Control Module (TCM), Transmission Control Module (TCM) harness is open or shorted, Transmission Control Module (TCM) circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code U1146 Description
What are the Possible Causes of the DTC U1146?
- Faulty Transmission Control Module (TCM)
- Transmission Control Module (TCM) harness is open or shorted
- Transmission Control Module (TCM) circuit poor electrical connection
How to Fix the DTC U1146?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the U1146 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the U1146 code?
Need more information on how to fix the U1146 code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the U1146 code diagnosed by a professional: Find a repair shop in your area
Information for Specific Makes
- U1146 Chrysler — Lost Communication With External Memory
- U1146 Dodge — Lost Communication With External Memory
- U1146 Jeep — Lost Communication With External Memory
Frequently Asked Questions about U1146 Code
No Frequently Asked Questions about U1146 Code found.
Discuss the causes and fixes for U1146 OBDII Code
-
Looks like you have a problem with the Transmission Control Module (TCM).
-
You have to replace the TCM. The TCM is behind the instrument panel, to the right of the left kick panel
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