U2105Network Communication

CAN Communication Bus - ECM Reset Detected

U2105 is a manufacturer-specific code indicating that a module detected the engine control module (ECM) reset or dropped off the CAN bus and came back. It often points to power, ground, or communication problems.

🚗 Depends. Repeated ECM resets can cause drivability issues, so diagnose it.
MEDIUM
severity
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🎯 Top Causes, Ranked by Likelihood

#1Poor power or ground to the ECM$50-$300
35%
Intermittent power or ground causes the ECM to reset.
#2Bus wiring or connector fault$50-$400
30%
Wiring problems interrupt ECM communication and trigger a reset code.
#3Failing ECM$300-$1200
20%
An internal ECM fault can cause resets.
#4Low system voltage$100-$400
15%
Weak battery or charging problems cause module resets.

🩺 Common Symptoms

💰 Repair Cost: DIY vs Shop

DIY Cost
$50-$400
Shop Cost
$150-$1200

📋 Free OBD2 Code Cheat Sheet

The 50 most common codes with likely cause and DIY fix cost. Sent once, no spam.

🔧 How to Diagnose U2105

1Check battery and charging system voltage
2Verify power and grounds at the ECM
3Inspect ECM wiring and connectors
4Scan for other communication codes stored with it

❓ Frequently Asked Questions

Can I drive with U2105?
It depends. Repeated ECM resets can cause stalling and drivability problems, so diagnose it.
What does an ECM reset mean?
A module saw the ECM drop off the bus and come back, usually from power, ground, or wiring issues.
What causes U2105?
Poor power or ground to the ECM, wiring faults, low voltage, or a failing ECM.

🔗 Related Codes

U2106U0100U1016U1000
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