Ye olde wiring harness? When to replace?
How do you know when to replace the harness?
Make some actual tests
Wait until it quits on the roadside?
Wait until smoke appears?
Read this MAD article:
http://www.madelectrical.com/electricaltech/amp-gauges.shtml
"It still works" might not be the best judge.
And of course, ya never know, maybe it does. But frankly that might be unlikely. Some "voltage drop" tests which look for
overcharging at the battery
under voltage at ignition
under voltage at headlights
would be something you can do, even with no experience, in less than 1/2 hour, which would give you an idea
The biggest list of problems with these cars is:
Problems with the bulkhead connector
Poor connections at ANY connector, top of the list is bulkhead, headlight switch, ignition switch, headlights themselves
Ammeter connections and problems with the ammeter itself
Poor connections in the fuse panel, both wire connections and fuse clips
Socket connections at lamps, park, tail, head
Rare, but sometimes failure of the "in harness splice"
The instrument cluster "as a whole" has it's own set
Broken / loose PC board connector pins, and or corrosion in the harness connector
loose stud nuts on the gauges
gauges out of cal
bad / out of cal voltage limiter
bad connections at the voltage limiter socket
