I have a case 580L backhoe and the altenator does not charge, I had it tested and it is good. I also checked out the instrament console and replaced the circuit board and clips and also replaced the burnt out bulbs. The other thing that dont work is the tach. Does the tach send power to the altenator to make it charge. Thanks everyone.
The tach gets its reading from one wire on the alternator. You say you tested the alternator and its good. You should get 14 or more volts at the battery post if the alternator is working. If your tach wire is broken but all other wires are good, your tach will still charge. You may have a faulty ground wire. That can cause both charging and tach functions to fail.
ERROR correction: If your tach wire is broken but all other wires are good, your alternator will still charge.
The charge lite should come on when you ground the small terminal that is closest to the block, the outer wire sends a signal to the tach. If the light dont come on you have a dash or wiring problem. For test purposes you can jump power to the inner small wire connection and force the alternator to charge which it will continue to do till the engine is shut off if it is in good condition. If the alternator has good power on the large red wire and does not charge when excited by jumping the exciter terminal with 12V with the engine running it is faulty.
check it out deeply maybe there will be any wire will not in the correct place ....
Nine times out of ten, this is a grounding problem. Don't trust any ground wires/lugs, even if they look ok. You can get corrosion inside the jacket without ever seeing it. Once the corrosion sets in, the resistance goes up. You can have what looks like a good physical connection, but in reality have a poor electrical connection. Check all ground wires, straps and connections with a multimeter/Ohmmeter. Also, check the back of the fuse block for rusty connectors. This is a common problem.
Thanks everybody for all the replys and the help I will let you know what I find when I get out there and check it out again.
Back to this thread, the circuit board copper at the notification lights on my dash cluster is getting thin. I discovered this by having intermittent charging issues that were resolved by shaking the clip in light. anyways, any recommendations on fixing the copper? Field fixes or someone that rebuilds them? Reminds me of a early 70's era ford instrument cluster with all the copper on green. Thank you
Measure the voltage drop, not the resistance. You won't find a bad connection or wire using an ohmmeter. The resistances are too small. When the circuit is operating measure the voltage drop. Ohm's law is Volts=Amps x Ohms. So ohms would be volts divided by amps. For example a circuit that operates at 25 amps and has a 3 volt drop, 3 volts divided by 25amps. This would be .12 ohms. You are not measuring that accurately with a handheld meter. In a starting circuit you could have 500amps or more flowing. When cranking you are at around 10volts in a good circuit. If you have a 2 volt drop on the ground of the power side you will crank slow or not at all. So 2 volts divided by 500 amps is .004 ohms. If you are unsure of how to measure a voltage drop Google it. There are some good YouTube videos with guys explaining it well. The key is the circuit has to be operating or attempt to be operating.
You can buy a new circuit board for less than $200.00 from a Case dealer.
Sequoia Equipment Fresno, said 2100$
Maybe the CB is a interchangeable component of the instrument cluster?
You need to determine which series 580l you have and which board you have in it. Your cb may have the part number embossed on it.
Thats great! Thank you