hitachi zaxis electrical problem

[Eddiebackblade]

I have a problem with my zaxis 160lc, the operator reported that it had 'clicked' twice on the starter before starting as normal.
It has continued to start normally with no problems, until he noticed two warning lights sticking on when the ignition is turned off.
The warning lights are oil and battery and give the impression the ignition is on, however upon turning the key the relays can be heard and the full set of warning lights operate along with the radio etc.

Upon investigating the only way to turn them off apart from disconecting the battery is remove the fuse marked 'sw box'.
I assume this is 'switch box' but cannot see the relavance to the illuminated lights.
If I remove the battery lead there is a fair spark indicating that something is definately pulling current.
Apart from the hassle of disconnecting the battery each night, everything else electrical works perfectly.
I have ordered a new ignition switch as it needed replacing anyway, and will fit a heavy duty battery isolator switch with removeable key in place of the sometimes problematic automatic Hitachi item.(good for security anyway)

Just wondered if anyone has experienced similar or has any ideas.

 

[AtlasRob]

Just wondered if anyone has experienced similar or has any ideas.

A very long time ago I encountered the same "lights on" when ignition was off, on an FH200.
From memory it was caused by the alternator, but why I honestly cant tell you, the company called on an auto spark that they used.
I cant remember if the alternator was replaced or not.

On a similar note, my last Atlas 1304M was dead on the key after being stopped for a very short while between concrete loads for no apparent reason.
I was told by the top Atlas tech to pull relay * and the machine started like it was brand new. My alternator had died. :beatsme
Be careful that you are not just running on battery power as when she stops next time it could be a right pain if you are in the wrong position.

 

[John C.]

On the older Hitachi excavators there was a diode installed behind the operator's seat that had to do with the glow plug circuit. Basically one of the glow plugs would short out and pull a big current that would burn out the diode. You could find this by checking for burn spots on the glow plug bar. A lot of times this problem would smoke the harness at the back of the engine.

The other issue was the alternators had an extra wire that worked a relay on the starter circuit. Basically when the alternator was turning there was a voltage on the extra wire which would cause the starter relay to open and not let the starter engage while the engine was running. That same wire also was tied to the monitor panel which turned the light out for engine oil pressure. The give away to the problem was the engine oil pressure light was on when the engine wasn't running. Many times the alternator would still put out the required charging voltage but the diode feeding this wiring was blown. It's easy to check. Turn the key on, don't start the engine and check the wire for voltage. Next disconnect the wire and try to start the engine. If it starts you need an alternator repair.

Good Luck!

 

[DarrylMueller]

Does your Hitachi Zaxis, have a ground disconect like Komatsu does? There is also a fuse-able link on Komatsu in case something like the ground disconect doesn't not work.
You will know if the disconnect doesn't work the engine will shut off but the rest of the electrical will be on like the control panel. Wack the disconnect with a hammer and it will disconnect. Tea Party 4/15/09

 

[JoeS1989]

Im having a similar problem with my 315C it recently had a new ignition fitted and now everytime i turn it off and take the key out the starter kicks in along with the computer screen and the radio etc.....get to get our fitter to look at it on monday!

 

[AtlasRob]

Many times the alternator would still put out the required charging voltage but the diode feeding this wiring was blown.
!

The mention of that wire and diode on the alternator definetly rings a bell.

 

[AtlasRob]

it recently had a new ignition fitted and now everytime i turn it off and take the key out the starter kicks in along with the computer screen and the radio etc.....!

Sounds like somebody has a wire on the wrong connector !

 

[Nac]

your alternater is not charging time to change. I just had this happen to my John Deere 160 battery light would stay on which means the alternator is not working properly. I swaped it out and it works fine. Also I bet you that your hour meter is not working also check it out.

 

[Monrad]

For the years that we have had Hitachi's the one thing that has been a weak leak has been the Alternater, dam things always go.

 

[Eddiebackblade]

I haven't had much time to look yet, but I did manage to remove all the wires from the Alternator and still the lights remained lit despite the ignition being off.
The ignition switch is not the best, so I have a new one to fit and hope this cures it. If not I'll have a dig at the Relays and a general check and after that it's a good local Auto electrician or Hitachi fitter.
Always a hard choice, do you let the cheaper electrician spend possibly longer to diagnose an unfamiliar machine or pay absolutely top dollar for the Hitachi fitter who should be able to diagnose it quicker?

 

[d4c24a]

ex135

eddie i had a problem on a ex135 ,that was a sod to fix
it would run for around 5 seconds with no dash lights
H M plant came out as machine was 15 months old
first thoughts were alternator ,then starter ,then various diaodes etc
finally a new computor was brought out
then a phone call to another fitter ,the main plug behind the seat to the right
(if sat in seat) was checked and one connection was bad in plug a jumper wire was put across plug and all was good and the new computor stayed in the box
cheers graham

 

[Eddiebackblade]

Latest update
finally managed to spend a little time on the problem.
I've fitted a new Ignition switch and a Key Isolator switch to replace the Automatic Hitachi version.(better security and you know it's actually off)
However no improvement.
I then pulled every Fuse and every Relay individually and still only the 'sw box' fuse will kill the ignition lights.
I have now however realised that all the ignition is staying on permanently, no just the two lights as initially thought.
Does anyone think it possible to get a backfeed from the starter as it was this initial starter ''clicking' not turning that started this whole episode off.
It seems to only feed the dash panel not the radio or heater which come on as normal when the key is turned.
The whole machine functions perfectly (every switch indicator light and function) and has operated for over 8 days with no problems apart from having to disconnect the battery to turn the ignition off at night.
Getting frustrating now, but could do without huge diagnostic costs at the moment. Don't mind paying for whatever is broken(Starter, Alternator, Computer) just don't like paying for someone to learn at my expense if you know what I mean.
If anyone knows a good Hitachi Electrics Man then please let me know.
Thanks Eddie

 

[ncbschzzt]

LoL this is a common problem, John C. said replace alternator this is not necessary. DO NOT replace the alternator thats the expensive fix, you can do a couple simple mods and all will be well. I will post your fix here in a minute. I want to give you an exact step by step repair.

 

[mathuranatha]

Does your Hitachi Zaxis, have a ground disconect like Komatsu does? There is also a fuse-able link on Komatsu in case something like the ground disconect doesn't not work.
You will know if the disconnect doesn't work the engine will shut off but the rest of the electrical will be on like the control panel. Wack the disconnect with a hammer and it will disconnect. Tea Party 4/15/09

Great tip about hitting the dissconect--- works real good , thanks .Now my old pc200-6Komatsu shuts down properly [with almost 20,000hrs on it ,when we got it for our rough bush farm].

Wont start with the key though . Have to put a screw driver across the starter motor terminals .Wonder if you have a tip for that?:notworthy

 

[d4c24a]

LoL this is a common problem, John C. said replace alternator this is not necessary. DO NOT replace the alternator thats the expensive fix, you can do a couple simple mods and all will be well. I will post your fix here in a minute. I want to give you an exact step by step repair.

any update on the common problem fix
cheers graham

 

[Johnny English]

If its any consolation, HM plant are cheaper than Finnings for service, last time we had a fitter from HM, its was £50 per hour and 85 pence per mile from nearest depot regradless of where fitter comes from, they should be able to plug on the palm top to your machine as well to computer diagnose, they couldn't do that to our old ex135, we got a £1,700 bill for transmission relay and finding the problem

 

[mathuranatha]

LoL this is a common problem, John C. said replace alternator this is not necessary. DO NOT replace the alternator thats the expensive fix, you can do a couple simple mods and all will be well. I will post your fix here in a minute. I want to give you an exact step by step repair.

Just wondering if the issue was resolved .My old pc200-6 is doing similar things .Ignition wont turn off , wont start with key [have to use a screwdriver across the starter terminals] and wont charge the batteries .Its an old beat up farm machine and taking the batteries home when every time I run it is cheaper than a technician
thanks ---- mat

 

[rush]

I have the same problem on my machine. Please keep us posted as to what you find out.

 

[Eddiebackblade]

I had no problem at all with the machine apart from the ignition lights not going out when switched off.
I was concerned of damage from welding and feared the computer and alternator.
However after 2 months of use no other problems occurred and this niggle never bothered me.
I always turn off and remove the key from the Isolator where posible on machines (finding a 580 Case burnt one morning not good! but valuable lesson) and fit a key Isolator if not standard to any machine I own.

However I was approached with an un-refuseable offer for the very clean Zaxis and had to get it sorted.
It ended with a local auto electrician who basically had a fiddle with everything but replaced nothing and it was sorted.
I suspect a dodgy multi plug or stuck relay, but was more than happy with the outcome.
The Zaxis has gone to a local guy who has had some 2 months fault free service, so all appears well.
As for the Zaxis replacement, it's taken some months of planning but should be breaking cover in early September once all the conversion work has been completed.

Electrical problems:beatsme:Banghead:bash

 

[RobVG]

I've had a similar problem with 2 of our ZAxis. Look for a hot wire that has rubbed through on one of the 3 long skinny bolts that hold the starter together.