Laser 4000 Intermitten problem

[Wally]

For the last couple of weeks the Laser has been shutting down due to the spray arch touching the passenger side of the car. So far there has been no vehicle damage. I have the virtual treadle and it seems to loose its memory. It`s doing it on spot fee rinse. Any help would be appreciated.

 

[madscientist]

first off, check the x30 prox switch, as it might be damaged. it's on the trolley, facing the exit side of the bay. over time it gets scuffed up from passing the frame, which over time gets rusty. you'll have to take it off to really see the face of it.

 

[Wally]

I checked the X30 prox switch and it looked good, no scratches. The gap was about a 1/4 inch and I moved in to 1/8. I`m thinking I might should go ahead and replace it and the cable just to eliminate this from possibly being the problem. What do you think? I also opened J3 and looked for corrosion on wires and didn`t find any.

 

[madscientist]

if you have another prox switch handy it might be worth a shot, since the next options are a little less likely to be the cause of your problem.
- bad prox cable, as you suggested
- a corroded pulse bar can cause intermittent measuring issues
- a bad festoon wire can also cause these issues

can you describe in a little more detail what is happening when it fails? is the trolley just not going far enough to the right before the bridge heads forward?

 

[Wally]

That`s right the trolley is not going far enough to the right before the bridge starts forward and the spray arch hits the mirror.

 

[lag]

Since it is not doing it on your first pass,your ultrasonics,and VT are probably OK. Your x23 input (trolley home) ,could be coming on. Have you had any other weird faults lately?

From what you are describing I would look at the x30,as you already have. A good test is to put it your VT board on position 3 ,and watch the pulse input on the VT ( #8 I believe). Put the machine like it is going down the drivers side ,put the x30 switch over a flag so it is on, then have someone drive the bridge up ,and down the rails,then light for the pulse input should stay on. If it blinks ,you have a festoon problem.

If it happens again pay attention to where the x30 switch is ,in relation to the counting flags , By this i mean is passed the first set of flags(drivers side) ,and into the second set ,of flags (passenger side), this can give an indication of what is going on.

One more question. Does this fault happen in bunches ,then go away ,is it just time to time?


I have also seen this happen when the trolley relay for the VT is not working ,check the wire connections,and make sure the relay is tightly plugged in.

 

[Wally]

It just does this occasionally, the last time was last Sunday. I had one fault where the spray arch wasn`t in home position and another spray arch hit while at home position (sometimes they leave before the spot free rinse comes on).

Thanks for the help.

 

[lag]

If you have checked ,or gone through the X30 (trolley prox) system. then you may need to consider that x23 (trolley home is the issue).If you have a spare switch just put it in ,and see if the problem goes away. Also if a little water can get into cable ends it will cause a false signal from time to time.

You may also need to check the prox cable connections,when the prox is on,wiggle the ends a little ,and see if the light on the switch goes out.

Basically x30 is going on and off to many times ,or x23 is coming on to soon.