DTC U0420:XX Invalid Data Received From The PSCM

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The PSCM receives messages from other modules through 2 connectors: the PSCM-A (or B) 3-pin connector at the gear and the multi-pin in-line connector in the engine compartment. The in-line connector receives messages from there other modules into the PSCM wiring harness. The PSCM wiring harness uses the VDB wiring to carry the messages from the in-line connector to the PSCM-A (or B) 3-pin connector. If any of the connector pins or VDB communication wires are loose or damaged, the PSCM cannot properly receive messages from other modules.
The PSCM receives messages from other modules through the PSCM 8-pin connector at the steering actuator and the multi-pin in-line connector in the engine compartment. The in-line connector receives messages from the other modules through the PSCM wiring harness. The PSCM wiring harness uses the VDB wiring to carry the messages from the in-line connector to the PSCM 8-pin connector. If any of the connector pins or VDB communication wires are loose or damaged, the PSCM cannot properly receive messages from other modules.

Possible Source	Action
Fuses Wiring, terminals or connectors Network communication concern 12-volt battery Charging system concern Module internal failure	GO to PINPOINT TEST BL