Thanks for the follow up Repairman and many Labatts Blues to you.

I finally found my problem!!?? After changing the micro switches, it worked for 2 days and the problem came back. No hydraulics. This time I measured the current at the hydraulic pump motor relay and read 36Volts. I manually pushed the relay contacts and the motor kicked in. I swiped the contactor with another forklift I have and everything came back to normal. I ended up ordering a new coil. It's been working all this past week like a charm. Just thought I'd let you know the end of my story.

Makes a lot of sense ! I will keep monitoring this unit to see how it behaves.
Thanks so much.

Repairman,
Those switches according to the manual are those finger type switches with the clear plastic cover mounted on the connecting bars between the lever assy and the control valve correct?

Why did cleaning them help? Like i said earlier it could have been trash or carboned up contacts and spraying them down cleaned the contacts enough to make them start working again. Or it could have been co-incidence and you moved a bad connection in the harness inadvertantly allowing it to start working again. One of the switches may have had a stuck contact and you freed it up.

There can be many reasons that caused this so nobody can definitively give you a full proof answer. But due to the nature of how these switches work i'm bank on one of the contacts being stuck and when you activated the circuit it caused it to error. But that's just an educated guess having dealt with these before.

I would order a couple and keep them on-hand just in case this happens again, then replace the bad one once you find it.

Thanks guys for the replies.
I will definitely be changing those micro switches. But still intrigued with why this is happening. Would it be because two switches happen to give or cut contact at once , provoking a hydraulic shut down ?
We have been using the forklift today and still working fine.
I guess it's like other things, where you just have to believe without understanding why !

yep edward is right
wd40 will contaminate the switch and then dirt will cause it to start sticking again.
Brake cleaner will dry out the oil in the bakolite material the switch is made of and make it extremely brittle. That goes for plastic/nylon parts as well.

The only thing any tech should be using to clean electrical components with is pressurized air or some type of electrical cleaner that is fast evaporating and preferably non-flammable, but I've found the non-flammable brands don't work quite as well. You just have to use air and dry the part off before applying current to it is all :o)

But i think you have located the culprit, by spraying something on them and the truck started working correctly tells the story.
If it were me i'd order new switches and replace those old sticky ones. ;o)

you guys do recognize that there is a slight fire hazard with spraying most of these lubricants/penetrating oils on electrical components doncha? and some of these (like older style brake cleaner), will make the plastic brittle in a few weeks after it dries out.

Well, I am pretty confident in WD-40 myself, but haven't always been so lucky with the hammer :)
But this afternoon, it surprised me a bit, and left me a little sceptical. I will be reassured in the coming days if the problem doesn't reoccur. I like it better when the fix is more tangible !
Regards.

Repairman, i keep a good supply of wd and pb on my truck and a 2 lb hammer to tap on things that don't work. Kind of like the old tv's that had the vertical hold going out and thats where my hammer fits in.

Thank's for the reply. There is no codes appearing on the display. The E40XM I am working on does not have the deluxe display dash with the touch pad. It's a 2001 model year without that option.
But this afternoon, I started looking at the series of micro switches on the hydraulic control levers. At a certain moment the hydraulics would start working for a few seconds. I sprayed WD-40 penetrating oil on the micro switches and everything went back to normal. They used the forklift for several hours since, and it's still working. Just hope it keeps up !

Repairman,
when it quits do you see any codes displayed on the dash display?
Also when the key is turned off you can press the star key (first button from the left) and it will flash any stored codes. There are 16 code slots per controller, first will be drive controller codes and then it will pause and then display the hydraulic controller codes.
Now for some reason if it does not go into the hydraulic error codes using the star key then press the last key on the right side.

If you want more detailed information like hour meter per code you'll need to hook up the laptop to it and pull the fault codes that way. The display only shows the error code and its description only.

Hi,
I was just wondering if you ever found your problem, because I have the same problem myself. It's a E40XM 36 v. Hydraulics work only when the battery is full charge. As soon as the battery goes down one notch the hydraulics quit. In other words, it works for about 5 minutes after unplugging charger!
Any ideas ?

Hey thanks swoop, will give your suggestions a try and let you know how it turns out.

if this truck has scr controlled hydraulics there is no contactor that controls the pump, it all goes through the scr panel. This is most likely an ev100 system and has 2 scr panels side by side. Now if this is the case there is a high possibility it also has a premium display panel, and even if it doesn't it still should be showing error codes in the display when any of the hydraulic functions are activated.

If there are no codes being displayed then first thing i would check are the main control (power) fuses on the power circuits. (the big block looking fuses connecting to the buss bars on the panel) There should be 2 of these fuses, one being a 325A and the other being a 500A, check those real close and make sure they are not blown out.
Next i would check the control fuses in the fuse block on the RH side of the panel, it should have several smaller fuses in it, they should be AGC type but sometimes they use ceramic ones, check those with a meter and also physically check the ones if they are glass and see if they are melted inside. Sometimes you can still get continuity across them and using a meter can fool you into thinking they are good when they still cannot carry the load and they open up during operation.

I would also check all the buss bar connections and make sure there are none burned, these would be obviously burned if they were loose and should be cleaned up and/or repaired.

you can also do what mike suggested too and check the signal on the pump control card at those locations on the terminals. Generally if there is a problem in this circuit it will display a code on the dash though.

just a few things to check for at first glance.

Check for ~ 12v at PB3 (Pump enable signal) check for 0v at TB2, TB3 or TB6 when you activate any lift/aux functions

Battery at 37.5 VDC

Charge the battery.