Iso Sae Reserved
U3100 — Iso Sae Reserved. It is a medium-severity fault: you can usually keep driving for short distances. The most common cause is damaged wiring, corrosion or a loose connector in the circuit.
"Not urgent today, but it won't fix itself either."
U3100 is a network diagnostic trouble code. It identifies a fault related to Iso Sae Reserved. The network/communication module monitors this circuit or component continuously and sets U3100 when the signal or value is outside the expected range, implausible or missing. This points to a communication or module fault that can affect one or more connected systems. The base function may still work, but performance can be affected, so the fault should be diagnosed. Diagnosis generally means inspecting the related wiring, connectors and power/ground references, then verifying the component against specification with a scan tool.
- Warning light(s) on the dashboard
- One or more connected systems may report faults
- Fault code stored in the control module
| # | Cause |
|---|---|
| 01 | Damaged wiring, corrosion or a loose connector in the circuit |
| 02 | Faulty sensor, actuator or component referenced by the code |
| 03 | Open, short or high resistance in the circuit |
| 04 | Poor power supply or ground reference to the component |
| 05 | Failed control module |
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Coming soonDealership car, motorbike, scootervehicles for saleNo technical service bulletins or recalls currently reference U3100. This section updates automatically when manufacturers publish related bulletins.
YES, WITH CAUTION — get it diagnosed as soon as possible.