Goofy voltage readings on 82 1100

Here's a doozie for you guys.

Voltage readings on brown wire coming up the frame to feed the front brake switch are 3.xx volts instead of the 12 that I'd expect. It also shows a .3 negative voltage reading for a bit when the key is shut off.

Rear switch voltage and operation is A-OK. All connectors on the bike have been cleaned and deoxidized. Brake switches work fine.

Any ideas?

The two switches should be wired in parallel so what you see at one, you should see at the other. When you are checking the voltage, is this with the wires to the switch disconnected?

Have yo looked at a wiring diagram? The brown wire powers a lot on the bike. Coming from the fuse panel, it makes several splices off to different equipment, R/R, Horns, front brake switch, Tach, speedo, fuel gauge, warning/ instrument lights. So if the power is there at the fuse panel, follow it along till it drops, un-plug the connectors for that leg, and check for a broken wire or poor connection.
If the Brown wire at the R/R is showing low voltage, the bike will overcharge and boil the battery, blow bulbs etc. It needs to be as close to battery voltage as possible. This is the sense wire for the R/R.
You can use the 81/82 K1/2 wiring from the service manual in my signature. It has the same system, electric gauges and all.

Motorhead is correct. You can check your regular bike voltage at the brown at the rectifier. If its all goofy, unplug things until you find the culprit.

Took Motor Head's advice and did some investigating on the wiring diagram. Found a junction point about a foot up the harness where the brown wire branches into 3 different leads.



Goofy-ass crimp joint was corroded to all hell and the feed wire for the brake switch was broken off. Once I got it un-taped the other two broke off.

Looks like over the years, water had puddled inside the rubber sleeving at just the right point in the harness to cook the joint to death.

Repaired the joint with solder, and inspected the other joints - found none bad. I did, however, find that either the brake light switch is sh_t and needs to be replaced, or the master needs to be rebuilt, as I had to push the brake lever forward with my hand to get the switch to disengage.

One thing leads to another I guess.

Watch these video's:


(Heatshrink Terminal Installation)


(Heatshrink Terminals And Connectors, AAA Protection)


(Heatshrinkable Crimpable Terminals)


(How to splice and repair wires, splicing techniques)

Wire Termination Insulation & Sizes

Terminal Insulation Color Wire Sizes
RED

---

22-18 gauge wire
BLUE

---

16-14 gauge wire
YELLOW

---

12-10 gauge wire
RED

---

8 Gauge
BLUE

---

6 Gauge
YELLOW

---

4 Gauge

The ring terminal holes comes in many sizes, from #4 up to 1/2" in most cases, it's a matter of finding the tightest fitting hole to fit the fastener for the termination.

American Wire Gauge(AWG) is backwards to what many people think; that is 22 gauge is many times smaller than 10 gauge even though the number is bigger.