B1304-04 Electronic Power Assisted Steering System - System Internal Failures: Action

WARNING: This page does not describe the selected car, but rather 12 other vehicles, including the 2017 Jaguar XJR, 2017 Jaguar XJ, 2016 Jaguar XJR, 2016 Jaguar XJ, and 2015 Jaguar XJR. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Once repair is complete, clear DTC's, close session and then upload SDD session file to JLR. Failure to follow this instruction may result in a warranty claim becoming invalid

Using the manufacturer approved diagnostic system, check datalogger signals - Main ECU Supply Voltage (0xDD02) - Vehicle Battery Voltage (0x402A). Refer to the applicable SYSTEM WIRING DIAGRAMS and check the power steering control module power and ground circuits and associated connectors for open circuit, high resistance. Repair or replace circuit(s)/connector (s) as required. Clear DTC and retest
Check if the timeframe of any stored DTCs coincides with customers' reports both of the onset of steering system fault symptoms and with the technical nature of the reported symptoms. If the time of DTC occurrence does not relate to the customer reported symptom, check for other appropriately timed and relevant DTCs in all vehicle modules. If the outcome of these investigations is not conclusive, contact the JLR Technical Helpdesk
If the steering gear fault persists, check and install a new steering gear as required