Load Sensing Proportioning Valve Test

NOTE: The vehicle must be unloaded, on a level surface, and not supported in any way, except by wheels.

Connect pressure gauges to the input and output side. On all models except Colt Vista, bleed brakes, then depress pedal to check if pressures meet specifications in BRAKE HYDRAULIC PRESSURE CHART. On Colt Vista, check pressure chart after depressing pedal, then go to step 5).

Fig 1: Measuring Hydraulic Pressure Illustration applies to 4WD diesel pickups.
On all models, with pedal depressed, open bleeder screw of LSPV. See Fig 1 . If both pressures are equal, fail safe system is operating.

If pressures are not within specification, loosen spring support bolt and adjust length of sensor spring. See Fig 2 .

SENSOR SPRING LENGTH

Application	In. (mm)
Sensor Spring	6.42-6.58 (163-167)

Fig 2: Load Sensing Proportioning Valve used on Pickup Loosen bolt to adjust the sensor spring length.

If adjustments do not meet specification, replace LSPV and sensor spring as a set.