Test D Pressure Modulator Valve (PMV) Assembly Continuity Test

D: Pressure Modulator Valve (PMV) Assembly Continuity Test:

ABS/TCS:

OPERATION: INLET/OUTLET VALVES:
^ Voltage is applied to the normally open inlet valves whenever the main relay is energized. An inlet valve closes when the EBCM/EBTCM supplies a ground path at the inlet valve control terminal. The EBCM/EBTCM closes an inlet valve for short periods to maintain (hold) or reduce pressure at a particular wheel.
^ The normally closed outlet valves operate similarly to the inlet valves. except that when the EBCM/EBTCM grounds an outlet valve, the valve opens instead of closes. The EBCM/EBTCM opens an outlet valve for short periods to reduce pressure at a particular wheel.

VALVE MODES
^ The pressure increase position is the operating valve position for normal (non-ABS) braking and traction control mode (when equipped). The EBCM/EBTCM does not energize either valve, leaving the inlet valve open and the outlet valve closed.

^ The pressure hold position occurs when the EBCM/EBTCM first notices an abnormal hydraulic pressure increase. This signifies an impending wheel lockup condition. The EBCM/EBTCM closes the corresponding inlet valve to avoid any additional hydraulic pressure increase (avoiding an ABS braking condition)
^ During a wheel lockup condition, the EBCM/EBTCM closes the inlet valve while pulsing open the outlet valve. This decreases hydraulic pressure at a specific wheel without decreasing overall system pressure. The reduced hydraulic pressure allows greater wheel spin, eliminating the wheel lockup condition.
^ DTC 41, 42, 45, 46, 51, 52, 55, or 56 sets when the (EBCM/EBTCM) detects an open or short to ground in the respective inlet or outlet valve circuit.

POSSIBLE CAUSES:
- Open in CKT 857, 858, 859, 861, 862, 863, 1290 or 1291.
- Short to ground in CKT 857, 858, 859, 861, 862, 863,1290 or 1291.