I changed the starter in my 83 300SD. Marked the top post wire and made sure to reconnect the same way on the new starter. Now I have no electrical at all. No start, no glow, no dome light, no headlight, no seatbelt buzzer, you get the picture. I don't even get the radio, which is a separate wire straight from the positive terminal.

The battery is new and fully charged.
Ground strap is about 5 years old and still looks shiny new.
Replaced the positive battery cable about five years ago as well.

With the battery connected I read 12.5 volts at the fuse box and at fender terminal strip.

With the battery disconnected:
Meter gives continuity between positve and negative cables.
Continuity between the battery cables, the starter posts, and the fender terminal strip.

Disconnected both wires to the starter. Continuity between the starter end of each wire and the fender box terminations.

Reconnected both starter wires. Still no electrical devices working.

Hooked up charger to the battery. Still no electrical devices working.

Ran a jumper cable between the negative battery terminal and the body ground strap. No change.

Just for a sanity check. The positive battery cable does connect to the top post of the starter solenoid, right?

Any suggestions on what to troubleshoot next?

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Greg Schwall

1983 300SD - 465,000 miles

I'm no auto electric expert, but I once upon a time purchased an off brand starter which caused problems. Once I installed a genuine Bosch starter, my problems ended.

Searching old threads and looks like my stupidity. Both cables go to the top post. Lower post is just the connection from the solenoid to the starter motor.

Don't know if I should blame my age failing eyesight or age failing memory.

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Greg Schwall

1983 300SD - 465,000 miles

Is that the terminal block under the Battery Tray?

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84 300D, 82 Volvo 244Gl Diesel

Terminal strip at passenger fender.

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Greg Schwall

1983 300SD - 465,000 miles

Definitely your memory. We discussed this the other night while we were over at the Casbah Lounge and Yak Conservatory having drinks.

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“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
― Brian P. Cleary, You Oughta Know By Now

Just remember that if the Feds come by asking about my whereabouts that night.

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Greg Schwall

1983 300SD - 465,000 miles

There is some wiring diagrams.
| Repair Guides | Wiring Diagrams | Wiring Diagrams | AutoZone.com

It would be a good idea to check for burned fuses.

The pic is of the terminal is under the battery tray. The pic shows how to hook up a remote starter. I don't know for sure but my best guess is that the fat white wire is the positive wire that goes to the same termina that the positive battery cable goes to on the starter motor.
I think if you are not getting positive voltage there you are not going to get voltage distribution to the rest of the car.
If you get a jumper wire from the positive battery terminal and apply it to the fat white wire you should get voltage to all of the stuff inside of the Car. If not you have a break/s in the circuit somwhere and that includes the Battery and Engine grounds.

The side with the yellow zero I believe the white wire goes to the small terminal on the Starter Motor and the purple/lavender wires go to the Glow Plug relay.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel

Congratulations on finding and repairing the problem. I don't care what anyone says, automobile electrical systems can be challenging. I just went through it with a dead battery situation on the 300D.

One thing that was learned was NEVER put dialectric grease on the connectors themselves. The grease acts as an insulator and that isn't a good thing. When I did it, I was in "stupid mode".