Safety Warning
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DTC P1631-81: Communication Error from ECM to VSC Invalid Serial Data Received [07/2020 - ]: Description
The skid control ECU (brake booster with master cylinder assembly) sends signals such as brake request signals to the hybrid vehicle control ECU. When the hybrid vehicle control ECU detects logic error signals sent from the skid control ECU (brake booster with master cylinder assembly) for a certain period of time, DTC P1631-81 is stored.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | DTC Output from |
|---|---|---|---|---|
| P1631-81 | Communication Error from ECM to VSC Invalid Serial Data Received | When the power switch is on (IG) and the dynamic radar cruise control system is operating, the hybrid vehicle control ECU detects logic error signals sent from the skid control ECU (brake booster with master cylinder assembly) for approximately 1 second or more. |
|
Radar Cruise1 |
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.