DTC 73: Fluid Level Switch Open Or Shorted

Fig 1: Presssure Modulator Monitoring System Schematic

Courtesy of GENERAL MOTORS CORP.

Pressure Modulator Valve (PMV) fluid level switch alerts EBCM/EBTCM to a low brake fluid condition in the PMV reservoir. Fluid level switch is located in the PMV reservoir. Fluid level switch is normally closed. When fluid level is low the switch opens, and EBCM/EBTCM turns on ANTI-LOCK indicator.

DTC 73 will set when EBCM/EBTCM detects a short to ground in circuit No. 848, 849, 853, or 1659. DTC 73 will also set if circuit No. 1451 is open.

Fig 2: DTC 73 Diagnostic Flow Chart

Courtesy of GENERAL MOTORS CORP.