Volvo EC 45 excavator voltage

[kthompson]

Good morning and pray each of you are doing great.

Been a while since have been here but back to topic that first brought me here, electric over hydraulic not working at least when first cranked up.

I have worked with the issue all these years mostly as my need for the machine had got less so was not worth pulling out 4 to 5,000 for the control panel Volvo shop was sure it was and then when I told them how the machine could sit there and run normally for few minutes it would power up and work fine they would say but that does not sound like control panel for when they fail it is total failure. So I keep hoping and hoping and well recently felt okay time to bite the bullet when control panel and thus the electrical system stopped after it had been working which had never done that. On a tractor forum someone suggested running new power and ground to the cab to see if it was not a connection issue so said now is the time to make that try. Well went to remove the ignition switch to see about running new power to it and the control panel lite up as it should when the switch rotated in the console. What? So I stopped and it worked fine for that day and two afternoons the next week and then last Friday and Saturday nothing so last evening removed the switch and checked the voltage to the power wire to it and grounded on the machine and I was shocked, it read from 3 to about 5.5 volts depending on which terminal I had the lead on. The quick thought was yep bad connection so need to run new power straight from the battery and a JD mechanic word came to my mind, some machines run real low voltage so be careful in trying to bypass anything. So that voice over came my I am so tired of it right now any thing would be an improvement to but not at the cost of control panel that may be fine. To make it worst I could turn the key on and the control panel powered up beautifully. I tried that several times and each time it worked fine. So I did what any average shade tree mechanic would do I left it! Wondering okay should I do what? It is now working with more movement of the ignition switch (it was in my hand with wires having been pulled off and reinstalled so possibly cleaning the terminals or go ahead and run direct wire with what may be higher voltage that burns it up or that supplies the proper voltage. That is when you all came to mind!!

Ask the pros if they know what the voltage to the ignition switch on a Volvo EC 45 should be? At present my thought is to spray the terminals and the switch with contract cleaner and reinstall and just see what happens and I will do that if a few more tries give 100% correct results. But the voltage still may be low due to bad connection or something between the power connection and the switch and I am at point now have the frame of mind it is time to repair or replace.

Thanks to each of you. Kenneth

 

[melli]

My machine panel is probably less complicated than yours (2003 331D)...what year is your machine?
I had a control panel that would flash when I tried to start machine...I eventually traced it down to the battery power cable to starter was shorting (vibrations over years had worn a hole in hot cable (+). Then last week, it started acting up again...dead battery (battery only a year old). The battery terminals looked clean, but I cleaned them and the post clamps, and I was back in business.
One of the biggest problems with electrical on these machines is the ground and hot cable running to frame and starter solenoid, respectively. Plus, making sure the battery posts are really clean. The ignition switch could certainly be gummed up with dirt and need a cleaning, but you should be getting 12v from the hot lead.
Lastly, does your control display diagnostic (trouble) codes? Mine can display a few....

 

[kthompson]

My machine is probably about same age. I talked with service manager at a Volvo shop today and he first said it should be 12 volts and then began to look (I was on the phone) at my machine circuit and came back with not sure it was truly 12 volt and the power for the switch came through the control panel. (note it is called control panel and I guess cause there are circuits in it that control the electrical system when runs the machine to me it is a very high price gauge display case.) I had thought about trying to just pull the control panel out, get transformer to reduce the voltage (if I can find out that the low voltage for everything is the same ) with a simple set of gauges even if much change out sending unit for engine oil pressure and temp. I really do not need the rest of the info it displays such as hyd pressure, low hyd oil temp, and hours on the machine.

It is really temping to just assume that system is 12v and try it...then if it burnt up all the valves understand you truly have a parts machine!!lol

 

[melli]

My machine is probably about same age. I talked with service manager at a Volvo shop today and he first said it should be 12 volts and then began to look (I was on the phone) at my machine circuit and came back with not sure it was truly 12 volt and the power for the switch came through the control panel. (note it is called control panel and I guess cause there are circuits in it that control the electrical system when runs the machine to me it is a very high price gauge display case.) I had thought about trying to just pull the control panel out, get transformer to reduce the voltage (if I can find out that the low voltage for everything is the same ) with a simple set of gauges even if much change out sending unit for engine oil pressure and temp. I really do not need the rest of the info it displays such as hyd pressure, low hyd oil temp, and hours on the machine.

It is really temping to just assume that system is 12v and try it...then if it burnt up all the valves understand you truly have a parts machine!!lol

You have to get a schematics of your machine...imho...will make life simpler.
I look at mine, and I see nothing but 12v...all the relays, fuses are geared for 12v.
Only one item is listed as 8v...and it is called a console sensor...whatever that is.

 

[kthompson]

Thanks will see if I can find one.

 

[kthompson]

I bought manual that proved to be a very complicated down load and finally with help of son in law who writes code got it working last night with I assume all Volvo machines on it. It is huge. Did not see right off anything showing the voltage but then was tired of fine print by the time got there and also forgot to look for voltage. Based upon what I found on an English forum I think found out Volvo has issues with ground connections causing issues like I am having. Based upon another call to the shop forum think he suspects that is also the issue, so then where are all the grounds to clean them up and be sure they are good for it looks like each wiring harness has it's own. Hope to work on this Saturday and with Ohm meeting can test to see which if any grounds have issue.

 

[lantraxco]

Change the switch first if you haven't. If it is switching logic level current instead of battery voltage it won't take much dirt or corrosion to mess up the connection of the contaces.

 

[kthompson]

I have sprayed the switch very heavy with contract cleaner but about 100% sure the ignition switch is not the issue. Voltage comes through the control panel to the switch and then back to the control panel, per service manager. I know the larger wire on the switch has no voltage to it when off and best I have found on it was about 5 volts and the control panel was working proper then.

 

[lantraxco]

I have not seen a key switch in my life you could clean the internal contacts without bending metal to open the switch up, and the key switch even at Vulva prices would be a couple orders of magnitude cheaper than a new panel or circuit board.

If the schematic doesn't call out voltages or test points, yeah start with grounds. One thing you can do is run a wire lead off the battery ground terminal to your meter negative and recheck voltages in the cab, might surprise you.