B2139
Moderate Severity (Level 3)Data Mismatch (receive data does not match what was expected)
B2139 usually means data Mismatch (receive data does not match what was expected).
Can you still drive with B2139?
⚠️Short-distance driving is usually OK, but have this diagnosed within a week to prevent further damage.
Typical repair cost: $100 – $1500
Severity Level 3 — Moderate
This code indicates a moderate issue that may affect vehicle performance and fuel economy. Continued driving is possible in most cases, but prompt diagnosis and repair are recommended to prevent further damage.
Common Symptoms
- Check Engine Light illuminated
- Various electronic systems behaving strangely — gauges, lights, and modules malfunctioning together
- Vehicle may not start or may stall unexpectedly
- Diagnostic trouble code (DTC) stored in module memory
Possible Causes
- Incorrect data being transmitted between modules — control module reporting data that doesn't match other sensor inputs
- Faulty control module sending invalid or corrupted data on the communication bus
- Wiring harness damage — twisted pair CAN bus wires shorted together or to power/ground
- Software bug or outdated calibration in the control module — check for available firmware updates
- Corroded module connector allowing moisture to short CAN bus wires — look for green/white corrosion at module pins
Common Fixes
- Scan vehicle with a professional-grade OBD2 scanner to read all stored codes and freeze frame data — note the conditions when the code set ($43-102 at shop, free at auto parts store for basic scan)
- Visually inspect the control module data communication wiring harness and connectors — look for chafed wires, melted insulation, green corrosion, loose pins, or rodent damage (often free to check yourself, $102 diagnostic fee at shop)
- Perform CAN bus resistance test — should read 60 ohms across CAN-H and CAN-L (two 120-ohm terminating resistors in parallel). If not, find the open or shorted CAN bus wire ($185-524 electrical diagnosis)
- Replace control module if testing confirms it has failed — use OEM quality, avoid the cheapest no-name aftermarket parts that fail in a year ($100-1500)
- Check and replace any blown fuses in the control module data communication fuse circuit — if fuse blows again, there's still a short that needs to be found ($5-19 for fuses)
Estimated Repair Cost
These are estimated costs based on generic repair data. Actual costs may vary depending on your vehicle, location, and labor rates.
Frequently Asked Questions
What does B2139 mean?
B2139 stands for "Data Mismatch (receive data does not match what was expected)". B2139 usually means data Mismatch (receive data does not match what was expected).
Can you drive with B2139?
Short-distance driving is usually OK, but have this diagnosed within a week to prevent further damage.
How much does it cost to fix B2139?
Repair costs for B2139 typically range from $100 to $1500, depending on your vehicle make, model, and local labor rates. Common fixes include: Scan vehicle with a professional-grade OBD2 scanner to read all stored codes and freeze frame data — note the conditions when the code set ($43-102 at shop, free at auto parts store for basic scan); Visually inspect the control module data communication wiring harness and connectors — look for chafed wires, melted insulation, green corrosion, loose pins, or rodent damage (often free to check yourself, $102 diagnostic fee at shop); Perform CAN bus resistance test — should read 60 ohms across CAN-H and CAN-L (two 120-ohm terminating resistors in parallel). If not, find the open or shorted CAN bus wire ($185-524 electrical diagnosis).
Will B2139 clear itself?
Explore Repair Costs
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