CUSTOMER CONCERN Brake system stores high-pressure accumulator DTCs C1234 and C1236. CAUSE No hydraulic leak or trapped air was found, confirming an internal failure of the Hydraulic Power Unit. CORRECTION Remove and replace the Hydraulic Power Unit, bleed the brake hydraulic system, perform brake-pedal travel and pressure-sensor calibrations, clear DTCs C1234 and C1236, and verify normal brake operation.

CUSTOMER CONCERN Customer requests diagnosis of hydraulic power unit primary-pressure sensor signal DTC C1237. CAUSE Confirmed internal failure of the hydraulic power unit caused improper pressure or an invalid internal pressure-sensor signal and set DTC C1237. CORRECTION Remove and replace the hydraulic power unit.