U0404-41 - Invalid Data Received From Gear Shift Control Module A - General checksum failure: Action

NOTE: If other engine system DTCs are set, perform the corrective actions for those DTCs first and retest.

Refer to the applicable SYSTEM WIRING DIAGRAMS and check the transmission control switch power and ground circuits for open circuit, high resistance. Repair the wiring harness as necessary
Using the Jaguar Land Rover approved diagnostic equipment, perform a CAN network integrity test. Refer to the applicable SYSTEM WIRING DIAGRAMS and check the high speed CAN bus (powertrain) circuit for short circuit to ground, short circuit to power, open circuit, high resistance. Repair the wiring harness as necessary
Using the Jaguar Land Rover approved diagnostic equipment, check the transmission control switch for related DTCs and refer to the relevant DTC index