Repair Actions/0031

See also: Errors and Secondary Error Codes

Note  This page is a technician's reference and is not intended to teach diagnosis and repair of electronic circuits.

This error has a different meaning on the Original Xbox 360 vs the Xbox 360 S and Xbox 360 E. It is not used on Xenon motherboards.

Original

ERROR_V_5P0_V_MEM

VREG_V5P0_VMEM_PWRGD is driven high by the V_5P0/V_MEM controller as long as the rail is within tolerance. If V_5P0 or V_MEM ever drops out of tolerance, the signal is de-asserted, causing the SMC to enter EC_FATAL and the 0031 code to be displayed on the front panel.

Short Circuit

• Check if V_5P0 or V_MEM are shorted
• If it is, check the rail to localize short
  • Lift at least 1 pin of the inductor to isolate the rails before checking
• If V_MEM is shorted, check decoupling capacitors near each RAM
• If all components are fine but a short on V_MEM remains, replace the RAM and/or GPU

Enable and Power Good

• Everything in this section must be checked quickly, as the SMC will shut down power upon entering EC_FATAL
• Check VREG_V5P0_EN and VREG_V1P8_EN signals and pulldowns
  • If pulldowns are fine but signal is missing, replace Southbridge
• Check VREG_V5P0_VMEM_PWRGD
  • If present, replace Southbridge
  • If missing, check pullup
    • If pullup is fine, continue below

VREG Circuit

• Everything in this section must be checked quickly, as the SMC will shut down power upon entering EC_FATAL
• Check if V_5P0 and V_MEM voltages are within tolerance
• If they are, replace the PWM driver and recheck PWRGD
• If they aren't, check VREG and PWM driver

S and E

ERROR_V_5P0

VREG_V5P0_PWRGD is driven high by the V_5P0 controller as long as the rail is within tolerance. If V_5P0 ever drops out of tolerance, the signal is de-asserted, causing the SMC to enter EC_FATAL and the 0031 code to be displayed on the front panel.

Short Circuit

• Check if V_5P0 is shorted
• If it is, check circuit components to localize short
  • Lift at least 1 pin of the inductor to isolate the rail before checking

Enable and Power Good

• Everything in this section must be checked quickly, as the SMC will shut down power upon entering EC_FATAL
• Check VREG_V5P0_EN signal and pulldown
  • If pulldown is fine but signal is missing, replace Southbridge
• Check VREG_V5P0_PWRGD
  • If present, replace Southbridge
  • If missing, check pullup
    • If pullup is fine, continue below

VREG Circuit

• Everything in this section must be checked quickly, as the SMC will shut down power upon entering EC_FATAL
• Check if V_5P0 voltage is within tolerance
• If it is, replace the PWM driver and recheck PWRGD
• If it isn't, check VREG and PWM driver