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DTC B1304-04: Electronic Power Assisted Steering System - System internal failures: Action

NOTE:
  • If the DTC  B1304-04 is present without any warning lamp illuminated, use the JLR  approved diagnostic equipment. Clear the DTC  (s) and retest. If the DTC  is still present, REFER to Diagnostic Trouble Code Index - Diagnostic Trouble Code Driver Assistance Domain Controller (DADC)  for any communication concerns.
  • If the either of the following warnings are displayed in the IPC  message center:
    • Emergency Braking and Emergency Steering not available
    • Ok to drive with caution Emergency Steering not available

    The warnings are not related to the power steering system. Check the Driver Assistance Domain Controller (DADC). Diagnostic Trouble Code Index - Diagnostic Trouble Code Driver Assistance Domain Controller (DADC)  for any communication concerns

  1. Check the PSCM  power and ground electrical circuits. GO to Pinpoint Test B .
  2. Using the JLR  approved diagnostic equipment, check Live Data - Main ECU Voltage Supply  (0xDD02) - Vehicle Battery Voltage  (0x402A). When the vehicle is stationary, move the steering from lock to lock in 2 seconds, immediately within 10 seconds from engine crank. If the main PSCM  voltage drops below 8.0 volts during the steering test, then install a new battery. Refer to: STARTUP BATTERY
  3. Check the battery system. Refer to: BATTERY
  4. Using the JLR  approved diagnostic equipment, clear the DTC  (s) and retest (Road test the vehicle for at least 10 minutes with a vehicle speed greater than 20 km/h (12 mph), including a full lock to lock of the steering system).
  5. Software update to PSCM  required
  6. If the fault persists and the power steering warning indicator illuminates, install a new steering gear. Refer to: STEERING GEAR
  7. Using the JLR  approved diagnostic equipment, re-configure the PSCM  with the latest level software