Diagnostic Aids

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The PSCM reporting only DTC B1D23:4B does not indicate a fault in the PSCM. It indicates an over-temperature condition due to ambient conditions or a heavy load on the EPAS system. An example of a heavy load would be multiple parking lot maneuvers over a short duration of time with low tire pressure or towing for long distances followed by multiple parking maneuvers.

The thermistor used by the PSCM is calibrated for 80°C (176°F) and as ambient temperature decreases, so does the accuracy of the sensor. At room temperature and lower, the sensor is +/- 20°C (68°F).

The presence of DTC B1D23:4B prevents the optional steering features; active park assist, Lane Keeping Assist (LKA) and Lane Centering Assist (LCA) from activating. If the DTC sets during an assist event, the event is terminated and the assist feature is deactivated.