DS 5000 stops in front!

We have a DS 5000 that fails in front every now and then. It is starting to happen more often. A car will pull in and it will spit on the car. The gantry never moves and then it tells the car to exit. This all takes about two seconds. The next car that comes in, the gantry starts moving forward and then fails in the front before it goes all the way down. Then we have to reset it.

When reset it may wash 10-40 cars perfectly then it fails again. Frustrating!

We have checked all sensors on the gantry, taken solenoid on hydraulic power pack apart, and taken pistons out of hydrolic power pack.

Can any help?

Thanks!

Sounds like it could be a weak laser eye.