DTC Advanced Diagnostics: P2531-00

DTC P2531-00 : Electric Servo Brake Control Unit Power Source Circuit (IG1) Low Voltage

NOTE

Initial Diagnosis:
The initial on-board diagnosis occurs right after the vehicle condition is turned to the ON mode, and the brake system indicator (red or amber) comes on, and continues until the indicator goes off.
Regular Diagnosis:
The regular on-board diagnosis begins right after the brake system indicator (red or amber) goes off, and it continues until the vehicle condition is turned to the OFF (LOCK) mode.
Review "How to Troubleshoot the Electric Servo Brake System" before doing the DTC troubleshooting procedure.
Test-drive the vehicle according to local traffic conditions and regulations. Do not test-drive on a lift unless specified.
The possible causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

Confirmation Procedure	Basic Condition: 12 volt battery voltage 9.55 - 16.72 V Operating Condition: Turn the vehicle to the ON mode.
Execution	Regular Diagnosis
Duration	About 2 second
DTC Type	1 drive cycle Brake system indicator (amber) on
Fail Safe Action	Stop regenerative brake function (Re-diagnose at the next IG-ON)
Possible Cause	Open or Short to ground between the electric servo brake control unit and the under-dash subfuse box B (IG1 ESB line) Blown fuse (Under-dash subfuse box B No. E1 (7.5 A)) Electric servo brake control unit internal circuit failure