755 No start, no electrics

Snowman9000 · Jun 26, 2009

I shut off my 755 in extremely hot weather yesterday. Went to restart and nothing. The idiot lights won't even come on.

I tested the battery with a load tester, and it passed with flying colors. I tested it through the battery clamps, did not remove the battery.

I checked the fuses I could find, which are four in a little fusebox on the firewall, and one by itself coming out of the wiring harness just behind that area, on the left side.

I removed the ignition switch and checked it with a multi-tester. It tests good. There is 12v coming to the switch on the red wire that goes to the Bat terminal on the switch. No corrosion on the terminals.

I am pretty sure that normally, the idiot lights will come on when the key is turned even if no one is sitting in the seat. I've checked the fuel gauge that way before. So I don't think it is a safety switch problem but I could be wrong.

What to check next? Thanks!

Ken Cunningham · Jun 26, 2009

I had a JD 1070 that did that to me once. If the fuses are all good, check for loose connections or corrosion on the ground wire. Mine was just a loose connection at the battery and i got it going in about 5 minutes. Let us know what you find. Good luck.

yankeerider · Jun 26, 2009

Might be obvious, but make sure your ground cable is actually sound at the end away from the battery. It's easy when testing to connect the negative at the battery, but that doesn't prove out the ground.

Snowman9000 · Jun 26, 2009

Cables look great at all ends. I can measure 12v at various points in the system away from the battery, such as the ignition switch, using a chassis ground. There is also 12v when the switch is "ON", at the fuse block.

lungdoc · Jun 27, 2009

Our 4320 Ehydro died suddenly mid brush-hogging last weekend, no dash etc. except if hazard/light switch turned. We pulled and re-inserted the relays and all worked fine. Still not entirely certain what happened (loose relay??) but it worked.

Snowman9000 · Jun 27, 2009

I stopped by the dealer and they printed off the wiring diagram and gave me some advice. I'm going to try a couple things and report back here.

MikeD74T · Jun 27, 2009

Snowman, Are you using a voltage or amperage tester at some of those points besides at the battery. i.e. Use your battery load tester at other points like starter solenoid to frame or battery + to outboard end of negative cable or frame, to see what's there for amps? I spent easily 4 hours this week chasing a problem that turned out to be a bad connection between the battery terminal clamp & the wire. Cut off the old clamp, bolted on a new one, & problem went away. DVM showed voltage everywhere which fooled me. MikeD74T

jd110 · Jun 27, 2009

There is a separate ground cable between the engine block and the frame. Check to be sure it is tight and not broken, They have a tendency to break fron the engine shaking on the rubber mounts.

Snowman9000 · Jun 28, 2009

Dealer pointed that out too, that using a multi-tester for voltage doesn't tell you anything about the load carrying quality of the connections involved. I returned the borrowed load tester. But I'll hand check and bypass some things until I get this. It cannot be too difficult, judging by the diagram. Famous last words.....

Snowman9000 · Jul 13, 2009

Turned out to be internal corrosion at the frame end of the negative battery cable. I had to replace the cable. It looked fine from the outside so I didn't try jumping it till late in the process.