CAT NRR40 - Design & Engineering discussion in Forkliftaction's forums (2024)

• Posted 27 Feb 2015 15:30
• Discussion started by Jerholz
• Texas, United States

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This has been on the back burner for a while, but I finally got back to troubleshooting the remote function. Here's what I've done so far.

I rang out all of the wires from the remote buttons on the mast to the hydraulic driver card. I rang out all of the wires I could find that had anything to do with the remote system between the hydraulic driver card and the Vehicle Manager (VM) and the Power Panel Driver Assy (PPDA). I ran the maintenance output tests to verify the P, PC, and 1S contactors function properly. Also, the output test for the 2nd solenoid, as that's whats used for remote lift. I think that verifies all of the necessary coils and coil drivers are OK.

The input test for the EPO (emergency power off) switch, which is the emergency stop switch on the remote panel was a little suspicious. The VM reads the switch as UP, even if the switch is depressed. I'm not sure if this would make it not work, but something may not be getting through to the VM. My truck does not have a "nested" switch.

The jumper TP1 on the PPDA has been removed, as indicated on the remote lift/lower electrical schematic.

Right now, I'm thinking it's a problem on the hydraulic driver card, but I've got a few questions someone here may know the answers to.

When I turn the key to remote, the panel down on the VM shows "10" during self test, then switches to "06". I can't find a list of VM display codes in the service manual. Anyone know how to interpret these?

I can't really tell from the schematics in the service manual how the UP function is supposed to function. What voltages should I be reading on the "remote lift", "remote", and "remote EPO" wires between the hydraulic driver assy and the VM when the UP buttons are pressed? Do I meter these against battery - ?

I'd like to post some of the schematics from the service manual, but it is copyrighted and the forum rules prohibit posting these.

Any other ideas?

Thanks in advance.

I haven't gotten a chance to get into it yet. I did get an operator's manual and the remote setup isn't mentioned, so I guess it was an option.

There are 150 ohm power resisters in line wth both the up and down circuits. I've located where the wires come in to the chassis. Shouldn't be too hard to ring them out once I get the time.

Thanks again for the input.

Your best bet is unplugging the battery and then find where the cable ends up in the chassis and try to unplug it there. Usually with just the battery unplugged you'll be ok. Use a multimeter and avoid using test lamps.

I'm 98% sure that's the Raymond setup. I'll see if I have a schematic tomorrow.

I'm out of town and don't have the serial number. The key switch has three positions; center off, right std, and left rmt. Around on the mast, there are a couple of handles. The right handle has two buttons, one for up and one for down. The left one has the same two, plus a red disconnect button. You have to push both up or down buttons simultaneously to make it work. This is to make sure your hands are clear of the moving parts. As I said, down works, but not up.

The mast cable does sound like the best place to start troubleshooting.

If the battery is disconnected, am I safe from arcing hazards? I.e, are there any capacitors in the system?

I've got an operator's manual on the way. It may have some information on how it's supposed to work.

Thanks for the replies.

more is coming back to me lol.

IIRC, it's in the main over the wire harness which I believe was a 6-18. Controlling the carriage valve (reach, tilt, sideshhift) and the remote functions. Not 100% sure though.

I have the EASI manual in paper at work. It's been a few years since my customer replaced these units.

As I sit here and think about it, and rereading Jerholz's issue, It does sound like the Raymond setup. It was simple, just had to depress both switches (one each grip) for the requested function.

Does it have a 3 position keyswitch? On the Raymonds it was:
Middle - off
Back - mast remote
Forward - operator compartment operation

Regardless, my first suspect with all carriage electronic issues (on any make of truck) would be the over the mast cable. The switches should be hooked up to a long cable that runs through the pulleys laced through the mast back to the computers in the chassis. These tend to break inside the insulation.

It's usually a 3 wire cable. Unplug the battery and ohm out all wires in the cable with a multimeter from the first termination point in the chassis to where it splits off to the grip switches. There should be screw down terminal boards (at least on the back of the grips plate on the carriage). Replace it if it's bad. You might even just find a broken crimp connector somewhere on either side.

It's probably an 18-3 cable (3 wires, 18 gauge each). Make sure it's stranded wire cable, not solid wire. I have a roll of it in my van but I forget the spec that I buy offhand. A good electrical supply house should be able to get the proper cable assembly.

Again, IIRC, while the wiring wasn't overly complicated, it wasn't exactly simple either. Kind of a pain too from what I remember as it's in a tight spot with the mast down.

I've seen Raymond reach trucks set up like this. I can't really remember how the presence switches were set up, but I do remember it involves depressing switches on both grips.

What year is this cat? Those Easi reaches were almost identical to some of the Cat reaches since, for a while, Raymond built reaches for MCFA. Might be the same setup for the option.

Thanks for the advice. I found a battery and charger locally for a little over twice what I'd have paid for a good set of cart batteries and charger. The battery is tested at 50% capacity and it's from a reputable local dealer. It should be more than adequate for my needs.

Any thoughts on the remote "up" function not working?

do not use golf cart batteries
the battery in these lifts is considered as the counterweight for the machine so using golf cart batteries would be a disaster in the making.
also the electrical system on these units is fairly sensitive and the golf cart batteries may work moving the truck around and working the hydraulics briefly but you will find out that they just will not work because of the high load the drive and hydraulic motors draw on the system and these batteries are just not capable of dealing with that under any kind of normal load.

DONT DO IT

you can find a reman battery for this truck for a reasonable price if you look around.